Quick plug-in self-sealing fuel filler neck and method

Abstract

The application discloses a kind of quick plug-in self-sealing oil filler connector and method, belong to fluid connector technical field;The connector includes fixed in fuselage and connected with oil filler pipe oil filler base and oil filler connector.Oil filler base is equipped with by spring and is pressed self-sealing cover, closed oil circuit under normal state.Oil filler connector includes main body, sealing assembly and inner core assembly.Through single screwing action, connector outer thread is engaged with the inner thread of base, sequentially complete: connector preliminary introduction, sealing assembly and base end surface pressure tight formation dynamic seal, inner core locking mechanism and base inner block engagement locking, and oil core is driven by thread and is finally pushed open self-sealing cover.The application integrates fixed, sealing and opening self-sealing valve into a continuous rotation operation, greatly simplifies unmanned aerial vehicle and extracts oil process, realizes quick, reliable, leak-free docking, especially suitable for the unmanned aerial vehicle operating scene with high operation efficiency and safety requirement.

Description

Technical Field

[0001] This invention belongs to the field of fluid connector technology, specifically relating to a quick-plug self-sealing oiling connector and method. Background Technology

[0002] For drones, especially medium and large-sized drones, refueling is a critical aspect of ground support. This requires refueling connectors to be quick to operate, reliably connected, and absolutely leak-proof throughout the refueling process to ensure the safety of personnel and equipment. Traditional aircraft or drone refueling connectors typically require multiple steps: first, aligning the connector with the refueling port; then, mechanically securing it using additional locking mechanisms (such as clamps, locking pins, or rotating rings); and finally, possibly manually or through another action, opening the self-sealing valve inside the refueling port. This step-by-step process is cumbersome, time-consuming, and carries the risk of fuel leakage due to improper timing or delayed sealing during connection and disconnection.

[0003] In existing technologies, some quick-connect fittings attempt to simplify operation, but they often fall short in terms of the reliability of rotary seals, the precise actuation of the internal valve core, and the coordination with self-sealing valves. Particularly in a single rotary motion, simultaneously addressing dynamic sealing under high torque, motion transition, and final opening is a design challenge. Therefore, there is an urgent need for a drone-specific refueling connector that is highly integrated, extremely easy to operate, and features multiple leak-proof designs. Summary of the Invention

[0004] The technical problem to be solved: To avoid the shortcomings of existing technologies, this invention provides a quick-plug self-sealing refueling connector and method, which can automatically and sequentially complete mechanical locking, dynamic sealing and oil circuit opening through a single twisting action, overcoming the defects of existing drone refueling connectors, such as multiple operation steps, low efficiency and potential leakage risks.

[0005] The technical solution of the present invention is: a quick-plug self-sealing refueling connector for refueling the fuel tank of a drone, comprising a refueling base fixedly installed on the drone body, and a refueling connector connected to the end of the refueling hose and detachably connected to the refueling base; The refueling base includes a refueling base body 1, a self-sealing cover 2, and a self-sealing spring 4. The refueling base body 1 contains, along its axial direction, a self-sealing cavity 1-3, a self-sealing inlet 1-5, and a threaded cavity 1-2 with internal threads. The self-sealing cavity 1-3 communicates with the inside of the fuel tank, and the threaded cavity 1-2 opens towards the outside of the machine body. The self-sealing cavity 1-3 and the threaded cavity 1-2 are connected through the self-sealing inlet 1-5. The self-sealing cover 2 is located at the self-sealing inlet 1-5. The self-sealing spring 4 applies an elastic force to the self-sealing cover 2, causing it to normally close the self-sealing inlet 1-5. The refueling connector includes a refueling connector body 5, a sealing component, and an inner core component. The refueling connector body 5 has an external thread 5-1 that engages with the internal thread of the threaded cavity 1-2. The sealing component is disposed inside the refueling connector body 5 and forms a first external environmental seal. It is used to abut and press against the end face of the refueling base body 1 during the screwing-in process of the refueling connector and to form a sealing fit before the self-sealing seat cover 2 is opened. The inner core component is disposed inside the refueling connector body 5 and includes a locking mechanism 10 and an oil outlet core 13 arranged coaxially. A second internal oil passage seal is provided between the inner core component and the refueling connector body 5, and an isolation seal is provided between the sealing component and the inner core component. The locking mechanism 10 is used to engage and lock with the locking block 1-6 inside the refueling base body 1 when the refueling connector is screwed into a predetermined position. After the sealing component forms a sealing fit, the oil outlet core 13 is driven by the thread to move axially relative to the refueling connector body 5 as the refueling connector body 5 continues to screw in, so as to open the self-sealing seat cover 2 and open the oil passage. During the screwing process, the sealing component contacts the inner end face of the oil filling base body 1 before the inner core component, so that the seal is established before the locking and valve opening actions; the oil filling connector completes the continuous operation of introduction, seal establishment, locking and opening of the self-sealing seat cover in sequence under a single screwing action.

[0006] A further technical solution of the present invention is: the refueling base body 1 is a cylindrical shell with one end open, wherein the self-sealing seat cavity 1-3 is located at the closed end, and its circumferential sidewall is provided with a plurality of self-sealing seat oil passage holes 1-4 for connecting to the inside of the oil tank; the outer edge of the open end is provided with a refueling base flange 1-1 for fixing the refueling base body 1 to the body of the drone. The refueling base body 1 has multiple self-sealing inlet blocks 1-6 arranged circumferentially on the end face of the self-sealing inlet 1-5 near the threaded cavity 1-2, which are used to engage and lock with the locking mechanism 10. The internal thread of the threaded cavity 1-2 of the refueling base has a lower tooth crest height than the complete tooth profile in the first tooth or the first two teeth near the opening end, forming an incomplete thread segment with a gradually deepening axial direction. This segment is used to guide the initial screwing of the external thread 5-1 and prevent the external thread from being jammed or damaged due to misalignment during the initial screwing. The preload force applied by the self-sealing seat spring 4 to the self-sealing seat cover 2 is greater than the static pressure generated by the fuel on the self-sealing seat cover 2 when the fuel tank connected to the fuel base body 1 is full, and less than the maximum axial thrust that the oil outlet core 13 can generate when it is screwed with a predetermined torque under thread drive.

[0007] A further technical solution of the present invention is: the main body 5 of the refueling connector is a stepped shaft structure with a central hole, the large diameter section of the stepped shaft has an external thread 5-1, the outer wall of the middle section is provided with anti-slip texture 5-2, and the small diameter section is an oil pipe connector 5-10 for connecting the refueling hose. The center hole of the refueling connector body 5 is a stepped hole. Its large diameter hole section serves as the inner cavity 5-6 and is connected to the small diameter hole section through the internal thread cavity 5-8. Its small diameter hole section serves as the inner cavity 5-9 of the oil pipe connector. The large-diameter section of the refueling connector body 5 has an annular outer cavity 5-3 coaxially formed on the outer periphery of the inner cavity 5-6; The bottom of the annular outer cavity 5-3 is provided with an outer cavity spring groove 5-7 for accommodating one end of the sealing bracket spring 7, and the inner side of its top is provided with a sealing bracket retaining ring groove 5-5; the bottom of the inner cavity 5-6 is provided with a locking mechanism spring groove 5-4 for accommodating one end of the locking mechanism spring 11; the sealing assembly is installed in the outer cavity 5-3 and forms the first external environment seal, the inner core assembly is installed in the inner cavity 5-6 and forms the second internal oil circuit seal, and the sealing bracket retaining ring 9 serves as an isolation seal between the first seal and the second seal.

[0008] A further technical solution of the present invention is: the sealing assembly includes a sealing bracket 6, a sealing bracket spring 7, a sealing bracket sealing ring 8, and a sealing bracket retaining ring sealing ring 9; The sealing bracket 6 is a hollow column with its bottom outer edge extending radially outward to form a retaining ring 6-1, which is movably inserted into the annular outer cavity 5-3 of the oil filling connector body 5, and the retaining ring 6-1 cooperates with the inner edge of the top of the annular outer cavity 5-3 to restrict the sealing bracket 6 from axially dislodging. The sealing bracket spring 7 is placed inside the annular outer cavity 5-3, with one end abutting against the outer cavity spring groove 5-7 and the other end abutting against the sealing bracket spring groove 6-2 provided at the bottom of the sealing bracket 6, and applying an elastic force to the sealing bracket 6 to make it extend out of the annular outer cavity 5-3; The sealing ring 8 of the sealing bracket is placed in the sealing ring groove 6-3 at the top of the sealing bracket 6, and is used to abut and seal with the inner end face of the refueling base body 1. The sealing bracket retaining ring 9 is placed in the groove 5-5 of the sealing bracket retaining ring, so that it is located between the side wall of the oiling connector body 5 and the sealing bracket 6, in order to achieve dynamic sealing between the two. In the initial state where the refueling connector components are not connected, the axial length of the sealing bracket 6 extending out of the outer cavity 5-3 is configured to be greater than the axial length of the locking mechanism 10 extending out of the inner cavity 5-6, so that when screwed in, the sealing ring 8 of the sealing bracket contacts and abuts against the inner end face of the refueling base body 1 before the locking mechanism protrusion 10-2; after the sealing ring 8 of the sealing bracket abuts against the inner end face of the refueling base body 1, the sealing bracket 6 stops rotating with the end face, and the refueling connector body 5 continues to rotate relative to the sealing bracket 6, and the sealing ring 9 of the sealing bracket achieves a rotational dynamic seal between the two.

[0009] A further technical solution of the present invention is that the inner core assembly further includes a locking mechanism spring 11; The locking mechanism 10 is a hollow cylinder with its bottom outer edge extending radially outward to form a locking mechanism retaining ring 10-1, which is movably disposed in the inner cavity 5-6 of the refueling connector body 5. The retaining ring 10-1 cooperates with the inner edge of the top of the inner cavity 5-6 to restrict the axial disengagement of the locking mechanism 10. The top end face of the locking mechanism 10 is provided with multiple locking mechanism protrusions 10-2 along the circumferential direction, which are used to interlock with the self-sealing inlet block 1-6 in the refueling base body 1 to achieve circumferential locking. A locking mechanism through hole 10-3 is opened at the center of the top end of the locking mechanism 10. The locking mechanism spring 11 applies an elastic force to the locking mechanism 10, causing it to extend out of the inner cavity 5-6. The elastic force is greater than the frictional force between the locking mechanism protrusion 10-2 and the self-sealing inlet block 1-6. The locking mechanism protrusion 10-2 has wedge-shaped guide slopes inclined towards the center of the tooth tip on both sides of its top. The corresponding mating surface of the self-sealing inlet block 1-6 has a slope that matches the wedge-shaped guide slope. This allows the locking mechanism protrusion 10-2 to be automatically guided into the gap of the self-sealing inlet block 1-6 by the circumferential rotational force generated by the slope when there is any circumferential deviation between the locking mechanism 10 and the self-sealing inlet block 1-6.

[0010] A further technical solution of the present invention is as follows: the oil outlet core 13 is divided into an oil outlet segment 13-1 and a threaded segment 13-2 along the axial direction; the radial cross-sectional shape of the oil outlet segment 13-1 matches the radial cross-sectional shape of the locking mechanism through hole 10-3, so that after the oil outlet core 13 is inserted into the locking mechanism through hole 10-3, it is circumferentially linked with the locking mechanism 10 and can slide relative to the axial direction; the threaded segment 13-2 is provided with an external thread, which is threadedly engaged with the internal thread cavity 5-8 of the oil filling connector body 5, and drives the oil outlet core 13 to move axially relative to the oil filling connector body 5 during the screwing-in process of the oil filling connector body 5.

[0011] A further technical solution of the present invention is: the locking mechanism through hole 10-3 is a cross-shaped hole with a circular center, and the radial cross section of the oil core section 13-1 is a cross shape of the same shape; the internal channel of the oil outlet core 13 is through, and the cooperation between the cross-shaped hole and the cross-shaped cross section simultaneously realizes the functions of circumferential linkage, axial guidance and central channel oil passage on a single interface; The upper side of the oil core section 13-1 is provided with multiple oil core holes 13-3. After the self-sealing seat cover 2 is opened, fuel flows through the internal channel of the oil core 13 and the self-sealing seat oil passage hole 1-4 into the fuel tank.

[0012] A further technical solution of the present invention is: the top end of the oil core segment 13-1 of the oil core 13 is a closed structure, and the upper half of the oil core segment 13-1 is provided with a plurality of oil core holes 13-3. The oil core holes 13-3 are distributed circumferentially on the side wall of the oil core segment 13-1, so that after the self-sealing cover 2 is pushed open, the fuel enters the internal channel of the oil core 13 radially or obliquely through the oil core holes on the side wall of the oil core segment, thereby avoiding the blockage of the oil passage when the self-sealing cover 2 is attached to the top end of the oil core 13; The oil outlet core 13 is initially in a retracted position. An oil outlet core head sealing ring 14 is provided between its top outer periphery and the inner wall of the locking mechanism 10 to seal the internal channel of the oil outlet core 13 before the self-sealing seat cover 2 is opened. The cross-section of the oil outlet core head sealing ring 14 is larger at the top and smaller at the bottom. Its radial thickness on the side near the top of the oil outlet core 13 is greater than the radial thickness on the side away from the top, so that when the oil outlet core 13 retracts axially relative to the locking mechanism 10 during disassembly, the outer peripheral surface of the oil outlet core head sealing ring 14 slides along the inner wall of the locking mechanism 10. The outer circumferential surface of the self-sealing cover 2 is provided with a self-sealing cover sealing ring groove 2-1 for installing the self-sealing cover sealing ring 3, which is used to seal the self-sealing inlet 1-5 under normal conditions; the cross-section of the self-sealing cover sealing ring 3 and / or the sealing bracket sealing ring 8 is convex.

[0013] A quick-plug self-sealing lubrication method includes the following steps: Screw in and introduce: Insert the oil filling connector into the threaded cavity 1-2 of the oil filling base and screw it in so that the external thread 5-1 of the oil filling connector body 5 engages with the internal thread of the threaded cavity 1-2. Move the oil filling connector axially until the sealing ring 8 of the sealing bracket at the top of the sealing bracket 6 abuts against the inner end face of the oil filling base body 1. Seal establishment: Continue to turn the oil filling connector, the sealing bracket spring 7 is compressed, and the sealing bracket 6 is gradually retracted into the annular outer cavity 5-3 of the oil filling connector body 5. Through the pressing fit between the sealing bracket sealing ring 8 and the end face of the oil filling base body 1, and the fit between the sealing bracket retaining ring 9 and the side wall of the sealing bracket 6, a seal is established between the oil filling connector and the oil filling base. Locking and motion conversion: Continue to turn the oil filling connector, the locking mechanism protrusion 10-2 at the top of the locking mechanism 10 and the self-sealing inlet block 1-6 in the oil filling base body 1 interlock and engage with each other to achieve circumferential locking. The locking mechanism 10 stops rotating, and the oil outlet core 13 stops rotating accordingly. Self-sealing opening: Continue to tighten the refueling connector. Due to the threaded engagement between the threaded section 13-2 of the oil outlet core 13 and the internal threaded cavity 5-8 of the refueling connector body 5, the oil outlet core 13 is driven to move axially relative to the refueling connector body 5. The top of the oil outlet core 13 pushes open the self-sealing seat cover 2, compresses the self-sealing seat spring 4, and opens the self-sealing inlet 1-5. Fuel flows into the internal channel of the oil outlet core 13 through the self-sealing seat cavity 1-3, completing the oil circuit connection.

[0014] A further technical solution of the present invention includes a disassembly step: The refueling connector is rotated in the reverse direction, causing the oil outlet core 13 to move axially in the opposite direction under the threaded drive, and the self-sealing seat cover 2 to close the self-sealing inlet 1-5 first under the action of the self-sealing seat spring 4; The refueling connector is then rotated in the reverse direction until the locking mechanism protrusion 10-2 disengages from the self-sealing inlet block 1-6; The sealing bracket 6 is then rotated in the reverse direction until it resets under the action of the sealing bracket spring 7, and the sealing ring 8 of the sealing bracket disengages from the end face of the refueling base body 1; The refueling connector is then rotated in the reverse direction until it is completely unscrewed from the refueling base.

[0015] The core of this invention lies not in a specific locking or sealing structure, but in the coordination between different mechanisms to automatically complete the sealing, circumferential limiting, and opening actions according to a predetermined sequence. This allows for the connection, sealing, locking, and opening of the oil filler connector using a single turning motion. Beneficial effects: The four functions of the refueling connector—introduction, seal establishment, circumferential locking, and self-sealing opening—are integrated into a single, continuous turning motion. The helical motion of the threaded joint drives each functional module sequentially according to a predetermined time sequence. Compared with existing technologies, this method offers the following specific advantages: 1. Extremely simplified operation, significantly improved efficiency A single, continuous "screwing in" or "screwing out" action is all it takes to automatically complete the entire sequence of operations, including connection / disconnection, sealing / unsealing, circumferential locking / unlocking, and oil circuit opening / closing. No step-by-step operations or additional locking actions are required, significantly improving the efficiency and convenience of drone refueling operations.

[0016] 2. Multiple sealing redundancy ensures excellent leak-proof performance. An innovative independent floating sealing assembly is incorporated, which takes effect early upon screwing in. This assembly establishes a complete seal before the self-sealing valve is opened, completely isolating the internal oil passage from the outside environment. Simultaneously, the movement of the sealing assembly is completely decoupled from the inner core assembly, ensuring that subsequent locking and valve opening actions do not disturb the established seal. Together with the self-sealing cap sealing ring, sealing bracket sealing ring, sealing bracket retaining ring, and oil outlet core sealing ring, four layers of sealing redundancy are formed, ensuring that the failure of any one seal does not affect the overall leak-proof performance.

[0017] 3. Close the valve before releasing the seal to reduce fuel leakage during disassembly. The oil outlet core is forcibly retracted by the threaded joint, and its axial retraction speed is greater than the reset speed of the sealing bracket, ensuring that the self-sealing cover closes first during disassembly, and the sealing bracket detaches from the end face only afterward. Throughout the disassembly process, the fuel is sealed within the self-sealing valve, and the oil circuit is completely cut off before the sealing assembly releases the seal, eliminating the risk of leakage at the moment of disassembly.

[0018] 4. Pure axial valve opening protects the sealing surface of the self-sealing valve. The self-sealing cover is opened by the oil outlet core pushing axially after it stops rotating. During the opening process, there is no relative rotation between the oil outlet core and the self-sealing cover, which avoids damage to the sealing surface and sealing ring of the self-sealing cover by torsional friction, and significantly extends the maintenance cycle and service life of the self-sealing valve.

[0019] 5. Timing is enforced by the structure, ensuring reliable operation and preventing misoperation. The timing of each component's operation is mandated by structural parameters such as the initial axial height difference between the sealing bracket and the locking mechanism, the engagement position of the teeth and the locking block, and the layered design of the elastic element's force value. Regardless of the operator's tightening speed or force, the sequence of sealing → locking → opening the valve will not be altered, fundamentally avoiding the risk of leakage due to improper operating timing. Attached Figure Description

[0020] Figure 1 The following is a general structural diagram (stage 1) of a quick-plug self-sealing oiling connector in an embodiment of the present invention; (a) overview, (b) 3D cross-sectional view, (c) cross-sectional view; Figure 2 These are partial cross-sectional views of different stages in an embodiment of the present invention. Figure 3 This is a schematic diagram of the structure of the refueling base body 1 in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the self-sealing cover 2 in an embodiment of the present invention; Figure 5 This is a schematic diagram of the structure of the self-sealing cap sealing ring 3 in an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of the self-sealing seat spring 4 in an embodiment of the present invention; Figure 7 This is a schematic diagram of the sealing bracket spring 7 in an embodiment of the present invention; Figure 8 This is a schematic diagram of the structure of the refueling connector body 5 in an embodiment of the present invention; Figure 9 This is a schematic diagram of the structure of the sealing bracket 6 in an embodiment of the present invention; Figure 10 This is a schematic diagram of the structure of the sealing ring 8 of the sealing bracket in an embodiment of the present invention; Figure 11 This is a schematic diagram of the structure of the sealing bracket retaining ring 9 in an embodiment of the present invention; Figure 12 This is a schematic diagram of the locking mechanism 10 in an embodiment of the present invention; Figure 13 This is a schematic diagram of the locking mechanism spring 11 in an embodiment of the present invention; Figure 14 This is a schematic diagram of the structure of the locking mechanism retaining ring sealing ring 12 in an embodiment of the present invention; Figure 15 This is a schematic diagram of the structure of the oil outlet core sealing ring 14 in an embodiment of the present invention; Figure 16 This is a schematic diagram of the structure of the oil outlet core 13 in an embodiment of the present invention; Explanation of reference numerals in the attached drawings: 1. Refueling base body; 1-1. Refueling base flange; 1-2. Refueling base threaded cavity; 1-3. Self-sealing seat cavity; 1-4. Self-sealing seat oil passage hole; 1-5. Refueling base self-sealing inlet; 1-6. Self-sealing inlet retaining block; 1-7. Self-sealing seat spring groove; 2. Self-sealing seat cover; 2-1. Self-sealing seat cover sealing ring groove; 2-2. Self-sealing seat cover spring groove; 3. Self-sealing cover sealing ring; 4. Self-sealing seat spring; 5. Refueling connector body; 5-1. Refueling connector external thread; 5-2. Anti-slip texture; 5-3. Outer cavity; 5-4. Locking mechanism spring groove; 5-5. Sealing bracket retaining ring sealing ring groove; 5-6. Inner cavity; 5-7. Outer cavity spring groove; 5-8. Refueling connector internal threaded cavity 5-9. Inner cavity of oil pipe joint; 5-10. Oil pipe joint; 6. Sealing bracket; 6-1. Sealing bracket retaining ring; 6-2. Sealing bracket spring groove; 6-3. Sealing bracket sealing ring groove; 7. Sealing bracket spring; 8. Sealing bracket sealing ring; 9. Sealing bracket retaining ring sealing ring; 10. Locking mechanism; 10-1. Locking mechanism retaining ring; 10-2. Locking mechanism protruding tooth; 10-3. Locking mechanism through hole; 10-4. Locking mechanism spring groove; 11. Locking mechanism spring; 12. Locking mechanism retaining ring sealing ring; 13. Oil outlet core; 13-1. Oil outlet core section; 13-2. Threaded section; 13-3. Oil outlet core hole; 13-4. Oil outlet core head sealing ring groove; 14. Oil outlet core head sealing ring. Detailed Implementation

[0021] The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.

[0022] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," 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.

[0023] To address the problems existing in the prior art, this invention proposes a quick-plug self-sealing refueling connector. For ease of description, the mounting surface of the refueling base is defined as the xy plane, and the displacement direction of the refueling connector when screwed in is the positive z-axis direction, which coincides with the connector's rotation axis.

[0024] The technical solution of the present invention will be further analyzed below with reference to the accompanying drawings: Reference Figure 1 As shown, a quick-plug self-sealing refueling connector includes a refueling base fixedly installed on the body of a drone, and a refueling connector connected to the end of the refueling hose.

[0025] 1. Fueling base Reference Figure 3 As shown, the refueling base consists of a refueling base body 1, a self-sealing cover 2, a self-sealing cover sealing ring 3, and a self-sealing spring 4.

[0026] The main body 1 of the refueling base is the main support structure, which is installed on the machine body (usually located at the bottom of the fuel tank with the opening facing downwards). Its structure, along the positive z-axis (from the outside of the machine body to the inside), consists of a refueling base flange 1-1, a refueling base threaded cavity 1-2, a refueling base self-sealing inlet 1-5, and a self-sealing seat cavity 1-3.

[0027] The refueling base flange 1-1 is an annular structure located on the outer edge of the open end of the refueling base body 1. It has multiple mounting holes evenly distributed along the circumference and is fixedly installed on the drone body by bolts. A sealing gasket is provided between the flange and the body to ensure the sealing of the mounting surface.

[0028] The threaded cavity 1-2 of the refueling base faces outwards from the machine body, and its inner wall is provided with internal threads for mating with the external threads 5-1 of the refueling connector body 5. The diameter of the threaded cavity 1-2 is larger than the diameter of the self-sealing seat cavity 1-3.

[0029] Preferably, the internal thread of the refueling base threaded cavity 1-2 has a lower tooth crest height than the complete tooth profile in the first tooth or the first two teeth near the opening end, forming an incomplete thread segment with a gradually deepening axial depth, which is used to guide the initial screwing in of the external thread 5-1.

[0030] The self-sealing seat cavity 1-3 is located at the deepest part of the main body 1 of the refueling base (the end in the positive direction of the z-axis) and is used to communicate with the inside of the fuel tank. Multiple self-sealing seat oil passage holes 1-4 are opened on the circumferential side wall of the self-sealing seat cavity 1-3, and fuel flows between the self-sealing seat cavity 1-3 and the fuel tank through the self-sealing seat oil passage holes 1-4.

[0031] Preferably, the plurality of self-sealing seat oil passage holes 1-4 are evenly distributed along the circumference of the self-sealing seat cavity 1-3, and the total flow cross-sectional area of ​​all self-sealing seat oil passage holes 1-4 is greater than 1.5 times the cross-sectional area of ​​the internal channel of the oil outlet core 13.

[0032] Preferably, the radius of the rounded corner of the oil passage hole 1-4 on one side of the inner wall of the self-sealing seat cavity 1-3 is not less than 0.2mm.

[0033] The threaded cavity 1-2 and the self-sealing seat cavity 1-3 are connected by the self-sealing inlet 1-5 of the oiling base.

[0034] On the side of the self-sealing inlet 1-5 near the threaded cavity 1-2, multiple self-sealing inlet blocks 1-6 are evenly distributed in a ring. The bottom inner end face of the self-sealing seat cavity 1-3 is provided with a self-sealing seat spring groove 1-7.

[0035] Reference Figure 4 As shown, the self-sealing cover 2 is a circular sealing cover located on the upper surface of the self-sealing inlet 1-5 (i.e., the positive z-axis side). Its diameter is larger than the diameter of the self-sealing inlet 1-5 but smaller than the inner diameter of the self-sealing cavity 1-3. A sealing ring groove 2-1 is provided on the side of the self-sealing cover 2 for installing the self-sealing cover sealing ring 3. A spring groove 2-2 is provided on the upper surface of the self-sealing cover 2 (positive z-axis side) to accommodate the other end of the self-sealing spring 4.

[0036] Preferably, the inner diameter of the self-sealing seat cover spring groove 2-2 is interference-fitted with the outer diameter of the end of the self-sealing seat spring 4 to prevent the end of the elastic element from coming out of the groove under vibration conditions.

[0037] Reference Figure 5 As shown, the self-sealing cap sealing ring 3 is installed in the sealing ring groove 2-1 on the side of the self-sealing seat cover 2. Its cross-section is preferably convex to enhance the sealing effect. The self-sealing cap sealing ring 3 is preferably made of oil-resistant fluororubber material, which has good media resistance, aging resistance and sealing performance.

[0038] Reference Figure 6 As shown, the self-sealing seat spring 4 is a compression helical spring, installed between the spring groove 2-2 of the self-sealing seat cover 2 and the self-sealing seat spring groove 1-7 of the oil filling base body 1. The self-sealing seat spring 4 is always in a compressed state, applying an elastic force towards the negative z-axis direction to the self-sealing seat cover 2, so that the self-sealing seat cover 2 is tightly pressed against the end face of the self-sealing inlet 1-5 through the self-sealing cover sealing ring 3, achieving a reliable seal under normal conditions.

[0039] The self-sealing seat spring 4 is configured to reach a coiled state or a preset minimum safe compression height when the self-sealing seat cover 2 is pushed open to the preset maximum opening position. At this time, the axial displacement of the self-sealing seat cover 2 is greater than or equal to the axial distance from the upper edge of the inlet of the self-sealing seat oil passage 1-4 to the end face of the self-sealing inlet 1-5, so that the self-sealing seat cover 2 completely opens the self-sealing seat oil passage 1-4, and fuel can enter the fuel tank unimpeded from the self-sealing seat cavity 1-3 through the self-sealing seat oil passage 1-4; at the same time, the self-sealing seat cover 2 cannot be pushed open further, and the continued screwing of the refueling connector body 5 is mechanically stopped. The operator feels a sudden increase in screwing resistance to judge that the refueling connector is fully in place and the oil circuit is fully open.

[0040] II. Fuel Connector The refueling connector consists of the refueling connector body 5, the sealing component, and the inner core component.

[0041] 1. Fuel filler connector body 5 Reference Figure 8 As shown, the main body 5 of the refueling connector is the main support structure, which is composed of two cylinders of different diameters connected together, namely the large cylinder end (the end closer to the refueling base component) and the small cylinder end (the end farther away from the refueling base component).

[0042] The large cylindrical end (near the refueling base): It has an external thread 5-1 for the refueling connector, which mates with the threaded cavity 1-2 of the base; internally, it has a coaxial annular outer cavity 5-3 and an inner cavity 5-6. The diameter of the outer cavity 5-3 is larger than the diameter of the inner cavity 5-6. The bottom of the annular outer cavity 5-3 has an outer cavity spring groove 5-7 to accommodate one end of the sealing bracket spring 7; the inner top has a sealing bracket retaining ring groove 5-5 for installing the sealing bracket retaining ring 9. The bottom of the inner cavity 5-6 has a locking mechanism spring groove 5-4 to accommodate one end of the locking mechanism spring 11.

[0043] The small cylindrical end (away from the refueling base): The exterior has anti-slip texture 5-2 for easy tightening. Inside the small cylindrical end, along the direction away from the large cylindrical end, there are sequentially arranged refueling connector internal thread cavity 5-8 and oil pipe connector internal cavity 5-9, communicating with the inner cavity 5-6. The inner wall of the refueling connector internal thread cavity 5-8 has internal threads for mating with the threaded section 13-2 of the oil outlet core 13. Correspondingly, the outer surface of the oil pipe connector internal cavity 5-9 forms an oil pipe connector 5-10. The outer wall of the oil pipe connector 5-10 has a barbed structure or external threads for connecting the refueling hose and securing it with a clamp or nut.

[0044] Preferably, the axial coverage of the anti-slip texture 5-2 is configured such that when the oil filling connector body 5 is fully screwed into the preset working position, one end of the anti-slip texture 5-2 near the oil filling base is flush with or has a predetermined axial relative position with the outer end face of the oil filling base flange 1-1, so as to provide the operator with a visual or tactile indication that it is screwed into place.

[0045] Preferably, the anti-slip texture 5-2 is an axial straight texture, which is provided on the transition outer wall between the large diameter section and the small diameter section of the oil filling connector body 5. The outer diameter of the transition outer wall is smaller than the outer diameter of the large diameter section and larger than the outer diameter of the small diameter section.

[0046] 2. Sealing assembly The sealing assembly consists of a sealing bracket 6, a sealing bracket spring 7, a sealing bracket sealing ring 8, and a sealing bracket retaining ring sealing ring 9.

[0047] Reference Figure 9 As shown, the sealing bracket 6 is a hollow cylinder, movably disposed within the annular outer cavity 5-3 of the oil filling connector body 5. The lower part (negative z-axis end) of the sealing bracket 6 is provided with a sealing bracket retaining ring 6-1, which engages with a retaining ring groove on the inner wall of the annular outer cavity 5-3, allowing the sealing bracket 6 to move axially and rotate around the axis only within the annular outer cavity 5-3, but preventing it from dislodging from the annular outer cavity 5-3. The bottom (negative z-axis end) of the sealing bracket 6 is provided with a sealing bracket spring groove 6-2, which, together with the outer cavity spring groove 5-7, limits the two ends of the sealing bracket spring 7. The top (positive z-axis end) of the sealing bracket 6 is provided with a sealing bracket sealing ring groove 6-3 for installing the sealing bracket sealing ring 8.

[0048] Preferably, the engagement of the retaining ring 6-1 of the sealing bracket 6 with the annular outer cavity 5-3 only restricts the axial disengagement of the sealing bracket 6, but does not restrict its circumferential rotation; when the sealing ring 8 of the sealing bracket abuts against the inner end face of the oil filling base body 1, the sealing bracket 6 stops rotating with the end face, and the oil filling connector body 5 continues to rotate relative to the sealing bracket 6, and the retaining ring 9 of the sealing bracket achieves a rotational dynamic seal between the two.

[0049] Reference Figure 7 As shown, the sealing bracket spring 7 is a compression helical spring, installed between the sealing bracket spring groove 6-2 and the outer cavity spring groove 5-7, applying an elastic force to the sealing bracket 6 to make it extend out of the outer cavity 5-3 (i.e. towards the positive z-axis direction).

[0050] Reference Figure 10 As shown, the sealing ring 8 of the sealing bracket is installed in the sealing ring groove 6-3 at the top of the sealing bracket 6. Its cross-section is preferably convex to enhance the sealing effect when it abuts against the end face of the oil filling base body 1. The sealing ring 8 of the sealing bracket is preferably made of oil-resistant fluororubber material.

[0051] Preferably, the convex cross-section of the sealing ring 8 of the sealing bracket is configured such that, during refueling, the fuel pressure in the threaded cavity 1-2 of the refueling base acts on the inner inclined surface of the wide portion of the convex cross-section, generating an axial component force that pushes the wide portion of the sealing ring 8 towards the inner end face of the refueling base body 1; during pumping, the external atmospheric pressure acts on the outer inclined surface of the wide portion of the convex cross-section, similarly generating an axial component force that pushes the wide portion towards the inner end face; thus, the sealing contact force increases with the increase of the internal and external pressure difference under both refueling and pumping conditions.

[0052] Reference Figure 11 As shown, the sealing bracket retaining ring 9 is installed in the sealing bracket retaining ring groove 5-5 of the oil filling connector body 5, and slides with the outer side wall of the sealing bracket 6 to achieve dynamic sealing between the sealing bracket 6 and the oil filling connector body 5, preventing oil from leaking from the gap between the sealing bracket 6 and the oil filling connector body 5.

[0053] Preferably, in the initial state where the refueling connector is not engaged, the axial length of the sealing bracket 6 extending out of the annular outer cavity 5-3 is configured to be greater than the axial length of the locking mechanism 10 extending out of the inner cavity 5-6, so that when screwed in, the sealing ring 8 of the sealing bracket contacts and abuts against the inner end face of the refueling base body 1 before the locking mechanism protrusion 10-2.

[0054] Preferably, the cross section of the sealing bracket retainer sealing ring (9) is a bidirectional sealing lip shape with an inner lip and an outer lip. The inner lip fits against the outer wall of the sealing bracket (6), and the outer lip fits against the inner wall of the annular outer cavity (5-3), providing a seal under both forward and reverse fluid pressure.

[0055] 3. Core Components The inner core assembly consists of a locking mechanism 10, a locking mechanism spring 11, a locking mechanism retaining ring seal 12, an oil outlet core 13, and an oil outlet core head seal 14.

[0056] Reference Figure 12As shown, the locking mechanism 10 is a hollow cylinder, movably disposed within the inner cavity 5-6 of the refueling connector body 5. A locking mechanism retaining ring 10-1 is provided at the lower part (negative z-axis end) of the locking mechanism 10. The retaining ring 10-1 engages with a retaining ring groove on the inner wall of the inner cavity 5-6, allowing the locking mechanism 10 to move axially and rotate around the axis within the inner cavity 5-6, but preventing it from dislodging from the inner cavity 5-6. Multiple locking mechanism protrusions 10-2 are evenly distributed along the circumferential tangential direction at the top (positive z-axis end) of the locking mechanism 10. The shape of the locking mechanism protrusions 10-2 matches the self-sealing inlet block 1-6 of the refueling base body 1, preferably with a trapezoidal cross-section, to facilitate interlocking and meshing. A locking mechanism through hole 10-3 is provided at the center of the top of the locking mechanism 10. This through hole consists of a central circular hole and multiple square holes evenly distributed around it, forming a cross-shaped hole. The inner top (positive z-axis end) of the locking mechanism 10 is provided with a locking mechanism spring groove 10-4, which together with the locking mechanism spring groove 5-4 of the oil filling connector body 5 limits the two ends of the locking mechanism spring 11.

[0057] Preferably, the locking mechanism through hole 10-3 is composed of a central circular hole and a plurality of rectangular grooves extending radially outward from the circular hole and evenly distributed circumferentially, forming a cross-shaped hole; the radial cross section of the oil core section 13-1 is a complementary cross shape, with a circular shaft at its center, and a protruding ridge extending integrally from the outer circumference of the circular shaft to slide in cooperation with the rectangular grooves; the internal channel of the oil outlet core 13 passes through the circular shaft.

[0058] Reference Figure 13 As shown, the locking mechanism spring 11 is a compression helical spring, installed between the locking mechanism spring groove 10-4 and the locking mechanism spring groove 5-4, applying an elastic force to the locking mechanism 10 to cause it to extend out of the inner cavity 5-6 (i.e., towards the positive z-axis direction). The elastic force of the locking mechanism spring 11 must be greater than the frictional force between the contact surface of the locking mechanism protrusion 10-2 and the self-sealing inlet block 1-6 to ensure that the locking mechanism protrusion 10-2 can smoothly insert into the self-sealing inlet block 1-6 and achieve complete engagement during the screwing process.

[0059] Reference Figure 14 As shown, the locking mechanism retaining ring 12 is installed on the outer ring of the upper surface of the threaded cavity 1-2 of the oil filling base (i.e., on the stepped surface between the threaded cavity 1-2 and the self-sealing inlet 1-5). It is used to form a seal with the lower end face of the locking mechanism retaining ring 10-1 when the locking mechanism 10 is in the highest initial position, so as to prevent oil from leaking from the gap between the locking mechanism 10 and the oil filling connector body 5.

[0060] The inner diameter of the locking mechanism retaining ring 12 is smaller than the outer diameter of the locking mechanism 10.

[0061] Reference Figure 16As shown, the oil outlet core 13 is a one-piece molded long rod-shaped component, which is divided into an oil core section 13-1 and a threaded section 13-2 along the axial direction, and has a cylindrical channel that runs through the entire length inside.

[0062] The cross-sectional shape of the oil core segment 13-1 is the same as that of the through hole 10-3 of the locking mechanism, being cross-shaped, allowing it to be inserted into the through hole 10-3 of the locking mechanism. This enables circumferential linkage with the locking mechanism 10 (i.e., when the locking mechanism 10 stops rotating, the oil core 13 also stops rotating) and relative axial sliding (i.e., the oil core 13 slides freely along the z-axis within the through hole 10-3 of the locking mechanism). Multiple oil core holes 13-3 are evenly distributed on the upper half (positive z-axis end) of the oil core segment 13-1. These oil core holes 13-3 penetrate the inner and outer walls of the oil core 13, allowing fuel to flow into the internal channel of the oil core 13 after the self-sealing cover 2 is opened. The top of the oil core segment 13-1 is a closed structure, ensuring that fuel can only enter the internal channel of the oil core 13 through the oil core holes 13-3. The top outer side of the oil core section 13-1 is provided with an oil outlet head sealing ring groove 13-4 for installing the oil outlet head sealing ring 14. Figure 15 ).

[0063] Preferably, the top of the oil core segment 13-1 is a closed structure, and the oil outlet hole 13-3 is distributed circumferentially on the side wall of the upper part of the oil core segment 13-1, so that after the self-sealing seat cover 2 is opened, fuel enters the internal channel radially or obliquely through the oil outlet hole on the side wall of the oil core segment.

[0064] Preferably, the axis of the oil outlet hole 13-3 forms an angle of 30° to 60° with the axis of the oil outlet core 13, and the oil inlet end of the oil outlet hole 13-3 faces the self-sealing seat cavity 1-3. In this way, the fuel enters the internal channel of the oil outlet core with an axial velocity component, reducing flow resistance.

[0065] Preferably, the ratio of the axial fitting length of the cross-shaped cross section of the oil core segment 13-1 to the cross-shaped hole of the locking mechanism through hole 10-3 to the circumscribed circle diameter of the cross-shaped cross section of the oil core segment 13-1 is 1.2 to 2.0. This ratio ensures that the oil core has a sufficiently long guide surface when sliding axially, preventing tilting and jamming, while not excessively increasing the sliding resistance, ensuring smooth pushing and retraction.

[0066] Preferably, the circumferential fit clearance between the cross-shaped cross-section of the oil core segment 13-1 and the cross-shaped cross-section of the locking mechanism through hole 10-3 is 0.05mm to 0.15mm. This clearance is small enough to ensure rapid circumferential linkage response without significant free travel, and large enough to ensure smooth axial sliding without jamming.

[0067] The outer wall of the threaded section 13-2 is provided with external threads, which mate with the internal threads of the internal thread cavity 5-8 of the refueling connector. During the rotation and screwing into of the refueling connector body 5, due to the threaded engagement, the oil outlet core 13 undergoes relative displacement along the z-axis relative to the refueling connector body 5.

[0068] The oil outlet sealing ring 14 is installed in the oil outlet sealing ring groove 13-4 at the top of the oil outlet core 13. When the oil outlet core 13 is in the initial lowest position, the oil outlet sealing ring 14 abuts against the inner wall of the locking mechanism 10 to form a seal, thus sealing the oil passage inside the oil outlet core 13.

[0069] Preferably, the cross-section of the oil outlet core sealing ring 14 is larger at the top and smaller at the bottom, and its radial thickness on the side closer to the top of the oil outlet core 13 is greater than that on the side farther from the top. This allows the outer circumferential surface of the oil outlet core sealing ring 14 to slide smoothly along the inner wall of the locking mechanism 10 during disassembly when the oil outlet core 13 retracts axially relative to the locking mechanism 10, without flipping or jamming.

[0070] III. Working Principle 1. Initial state (non-working state): Initial state of the refueling base: Under the elastic force of the self-sealing seat spring 4, the self-sealing seat cover 2 seals the self-sealing inlet 1-5 through the self-sealing cover sealing ring 3. At this time, the oil in the tank enters the self-sealing seat cavity 1-3 through the self-sealing seat oil passage 1-4, but is blocked by the self-sealing seat cover 2 and the self-sealing cover sealing ring 3, and cannot overflow through the inlet 1-5.

[0071] Initial state of the oil filling connector: The sealing bracket 6, under the elastic force of the sealing bracket spring 7, is at its highest position extending out of the outer cavity 5-3 (the extreme position in the positive z-axis direction). The locking mechanism 10, under the elastic force of the locking mechanism spring 11, is at its highest position extending out of the inner cavity 5-6 (the extreme position in the positive z-axis direction). The oil outlet core 13 is at its lowest point of travel. Under the combined action of the locking mechanism 10, spring 11, sealing ring 12, and oil outlet core 13 and sealing ring 14, the oil passage inside the oil outlet core 13 is sealed.

[0072] 2. Oiling operation (screwing process): Screw the refueling connector into the base. This process can be divided into four consecutive stages, such as... Figure 2 As shown: Phase 1: Initial Rotation Stage The external thread 5-1 of the refueling connector begins to screw into the threaded cavity 1-2 of the refueling base until the upper end of the sealing bracket 6 reaches the inner upper surface of the threaded cavity 1-2 of the refueling base through the sealing ring 8. At this time, the stroke of the main body 5 of the refueling connector is a. During this stage, all components rotate around the z-axis with the main body, and neither the sealing bracket spring 7 nor the locking mechanism spring 11 deforms. The locking mechanism protrusion 10-2 has not yet contacted the self-sealing inlet block 1-6.

[0073] Phase Two: Sealing Establishment Phase The refueling connector continues to screw in until the upper end face of the locking mechanism protrusion 10-2 contacts the self-sealing inlet block 1-6. Since the sealing ring 8 of the sealing bracket was already pressed against the upper end face of the base in the first stage, the sealing bracket spring 7 is compressed in this stage, and the sealing bracket 6 gradually retracts into the outer cavity 5-3. Through the pressing fit between the sealing ring 8 of the sealing bracket and the upper end face of the base, and the fit between the sealing ring 9 of the sealing bracket and the side wall of the sealing bracket 6, the sealing components completely isolate the inner core components from the outside, achieving a reliable seal and preventing oil leakage. In this stage, the stroke of the refueling connector body 5 is b, and the total stroke is a+b; the locking mechanism spring 11 remains unchanged. The displacement of the sealing bracket 6 relative to the refueling connector body 5 is b, while it remains stationary relative to the refueling base body 1. During this process, except for the sealing bracket 6, all other components rotate around the z-axis with the body.

[0074] Phase Three: Locking and Movement Transition Phase As the refueling connector continues to screw in, the locking mechanism's protruding teeth 10-2 and the self-sealing inlet block 1-6 interlock and engage, achieving circumferential locking, and the locking mechanism 10 stops rotating around the z-axis. Because the elastic force of the locking mechanism spring 11 is greater than the frictional force between the contact surfaces of the protruding teeth and the block, the engagement between the two gradually deepens until they are fully engaged.

[0075] In this stage, both the sealing bracket spring 7 and the locking mechanism spring 11 are compressed, the sealing bracket 6 further retracts into the outer cavity 5-3, and the locking mechanism 10 begins to retract into the inner cavity 5-6. Because the cross-sectional shape of the oil core section 13-1 matches the through hole 10-3 of the locking mechanism, the oil outlet core 13 and the locking mechanism 10 cannot rotate relative to each other. Therefore, after the locking mechanism 10 stops rotating, the oil outlet core 13 also stops rotating. As the refueling connector body 5 continues to screw in, the threaded section 13-2 engages with the threaded cavity 5-8 of the refueling connector, driving the oil outlet core 13 to translate positively along the z-axis relative to the refueling connector body 5.

[0076] The endpoint of this stage is: the top of the oil outlet core 13 just contacts the lower surface of the self-sealing seat cover 2, and at the same time, the locking mechanism protrusion 10-2 is fully engaged with the self-sealing inlet block 1-6. Define the stroke of the refueling connector body 5 in this stage as c, and the total stroke as a+b+c; the absolute displacement of the oil outlet core 13 in the z direction is f1, and the relative displacement of the oil outlet core 13 in the z direction relative to the refueling connector body 5 is f2. Then, f1-f2=c, and f2 / c is equal to the ratio of the pitch r1 of the threaded section 13-2 of the oil outlet core to the pitch r2 of the threaded cavity 1-2 of the refueling base, that is, f2 / c=r1 / r2.

[0077] Phase Four: The Stage of Opening Up and Self-Sealing The fuel filler connector continues to screw in the last stroke d. The fuel outlet wick 13 continues to move in the positive z-axis direction, overcoming the elastic force of the self-sealing seat spring 4 to open the self-sealing seat cover 2. At this point, the fuel passage is fully open: fuel flows from the fuel inlet 1-4 of the self-sealing seat into the self-sealing seat cavity 1-3, enters the threaded cavity 1-2 of the fuel filler base through the opened self-sealing inlet 1-5, then flows into the internal channel of the fuel outlet wick 13 through the fuel outlet wick hole 13-3, and finally enters the fuel filling line.

[0078] In this stage, the sealing bracket spring 7 and the locking mechanism spring 11 continue to be compressed, the sealing bracket 6 further retracts into the outer cavity 5-3, and the locking mechanism 10 further retracts into the inner cavity 5-6. The stroke of the refueling connector body 5 in this stage is d, and the total stroke is a+b+c+d. The absolute displacement of the oil outlet core 13 in the z-direction is f3, and its displacement relative to the refueling connector body 5 is f4. Therefore, f3-f4=d, and f4 / d=f2 / c=r1 / r2. The stroke by which the self-sealing cover 2 is pushed open is f3.

[0079] 3. Disassembly operation (screwing process): Tighten the connector in reverse order, performing the four stages mentioned above in reverse sequence: First, the main body 5 of the refueling connector moves along the negative z-axis. The oil outlet core 13 moves relative to the main body 5 of the refueling connector in the negative z-axis direction (i.e., retracts) under the thread drive. The self-sealing cover 2 closes the self-sealing inlet 1-5 first under the elastic force of the self-sealing spring 4, restoring the seal.

[0080] Subsequently, the refueling connector body 5 continues to move in the negative z-axis direction, the locking mechanism protrusion 10-2 disengages from the self-sealing inlet block 1-6, and the locking mechanism 10 resets under the elastic force of the locking mechanism spring 11.

[0081] Next, under the elastic force of the sealing bracket spring 7, the sealing bracket 6 returns to its original position and extends out of the annular outer cavity 5-3, and the sealing ring 8 of the sealing bracket disengages from its contact with the upper inner surface of the refueling base body 1.

[0082] Finally, the external thread 5-1 of the refueling connector component is completely unscrewed from the internal thread of the refueling base threaded cavity 1-2, and the refueling connector component is completely separated from the refueling base component. Throughout the disassembly process, because the self-sealing cover 2 closes first after the oil outlet core 13 retracts, and the seal of the sealing component is only released after the locking mechanism is disengaged, there is no fuel leakage throughout the entire process.

[0083] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention.

Claims

1. A quick-plug self-sealing refueling connector for refueling drone fuel tanks, characterized in that: It includes a refueling base that is fixedly installed on the drone body, and a refueling connector that is connected to the end of the refueling hose and detachably docked to the refueling base; The refueling base includes a refueling base body (1), a self-sealing cover (2), and a self-sealing spring (4); the refueling base body (1) is provided with a self-sealing cavity (1-3), a self-sealing inlet (1-5), and a threaded cavity (1-2) with internal threads in sequence along the axial direction. The self-sealing cavity (1-3) is connected to the inside of the fuel tank, and the opening of the threaded cavity (1-2) faces the outside of the machine body. The self-sealing cavity (1-3) and the threaded cavity (1-2) are connected through the self-sealing inlet (1-5); the self-sealing cover (2) is located at the self-sealing inlet (1-5); the self-sealing spring (4) applies an elastic force to the self-sealing cover (2) so that it normally closes the self-sealing inlet (1-5). The refueling connector includes a refueling connector body (5), a sealing component, and an inner core component; the refueling connector body (5) has an external thread (5-1) that engages with the internal thread of the threaded cavity (1-2); the sealing component is disposed inside the refueling connector body (5) and forms the first external environmental seal, used to abut and press against the end face of the refueling base body (1) during the screwing-in process of the refueling connector, and to form a sealing fit before the self-sealing seat cover (2) is opened; the inner core component is disposed inside the refueling connector body (5) and includes a locking mechanism (10) coaxially disposed inside the refueling connector body (5). The inner core assembly and the oil supply connector body (5) are provided with a second internal oil passage seal, and the sealing assembly and the inner core assembly are provided with an isolation seal; the locking mechanism (10) is used to engage and lock with the locking block (1-6) in the oil supply base body (1) when the oil supply connector is screwed into the predetermined position; after the sealing assembly forms a sealing fit, the oil supply connector (13) is driven by the thread to move axially relative to the oil supply connector body (5) as the oil supply connector body (5) continues to be screwed in, so as to open the self-sealing seat cover (2) and open the oil passage; During the screwing process, the sealing component contacts the inner end face of the oiling base body (1) before the inner core component, so that the seal is established before the locking and valve opening actions; the oiling connector completes the continuous operation of introduction, seal establishment, locking and opening of the self-sealing seat cover in sequence under a single screwing action.

2. The quick-plug self-sealing oiling connector according to claim 1, characterized in that: The refueling base body (1) is a cylindrical shell with one end open, wherein the self-sealing seat cavity (1-3) is located at the closed end, and its circumferential sidewall is provided with a plurality of self-sealing seat oil passage holes (1-4) for connecting to the inside of the oil tank; the outer edge of the open end is provided with a refueling base flange (1-1) for fixing the refueling base body (1) to the drone body; The main body (1) of the refueling base has multiple self-sealing inlet blocks (1-6) arranged circumferentially on the end face of the self-sealing inlet (1-5) near the threaded cavity (1-2) for engaging and locking with the locking mechanism (10); The internal thread of the oiling base thread cavity (1-2) has a lower tooth crest height in the first tooth or the first two teeth near the opening end than the tooth crest height of the complete tooth profile, forming an incomplete thread segment with a gradually deepening axial direction. This segment is used to guide the initial screwing in of the external thread (5-1) and prevent the external thread from being jammed or damaged due to misalignment during the initial screwing in. The preload force applied by the self-sealing seat spring (4) to the self-sealing seat cover (2) is greater than the static pressure generated by the fuel on the self-sealing seat cover (2) when the oil tank connected to the oil base body (1) is full, and less than the maximum axial thrust that the oil outlet core (13) can generate when it is screwed with a predetermined torque under the thread drive.

3. The quick-plug self-sealing oiling connector according to claim 2, characterized in that: The main body (5) of the refueling connector is a stepped shaft structure with a central hole. The large diameter section of the stepped shaft has an external thread (5-1), the outer wall of the middle section is provided with anti-slip texture (5-2), and the small diameter section is an oil pipe connector (5-10) for connecting the refueling hose. The center hole of the refueling connector body (5) is a stepped hole. Its large diameter hole section serves as the inner cavity (5-6) and is connected to the small diameter hole section through the internal thread cavity (5-8). Its small diameter hole section serves as the inner cavity (5-9) of the oil pipe connector. The large-diameter section of the refueling connector body (5) has an annular outer cavity (5-3) coaxially formed on the outer periphery of the inner cavity (5-6). The bottom of the annular outer cavity (5-3) is provided with an outer cavity spring groove (5-7) for accommodating one end of the sealing bracket spring (7), and the inner side of its top is provided with a sealing bracket retaining ring groove (5-5); the bottom of the inner cavity (5-6) is provided with a locking mechanism spring groove (5-4) for accommodating one end of the locking mechanism spring (11); the sealing assembly is installed in the outer cavity (5-3) and forms the first external environment seal, the inner core assembly is installed in the inner cavity (5-6) and forms the second internal oil circuit seal, and the sealing bracket retaining ring (9) serves as an isolation seal between the first seal and the second seal.

4. The quick-plug self-sealing oiling connector according to claim 3, characterized in that: The sealing assembly includes a sealing bracket (6), a sealing bracket spring (7), a sealing bracket sealing ring (8), and a sealing bracket retaining ring sealing ring (9). The sealing bracket (6) is a hollow column with its bottom outer edge extending radially outward to form a retaining ring (6-1), which is movably inserted into the annular outer cavity (5-3) of the oil filling connector body (5), and the retaining ring (6-1) cooperates with the inner edge of the top of the annular outer cavity (5-3) to restrict the sealing bracket (6) from axially dislodging; The sealing bracket spring (7) is placed in the annular outer cavity (5-3), with one end abutting against the outer cavity spring groove (5-7) and the other end abutting against the sealing bracket spring groove (6-2) provided at the bottom of the sealing bracket (6), and applying an elastic force to the sealing bracket (6) to make it extend out of the annular outer cavity (5-3); The sealing ring (8) of the sealing bracket is placed in the sealing ring groove (6-3) at the top of the sealing bracket (6) for sealing against the inner end face of the refueling base body (1). The sealing bracket retainer sealing ring (9) is placed in the groove (5-5) of the sealing bracket retainer sealing ring, so that it is located between the side wall of the oiling connector body (5) and the sealing bracket (6) to achieve dynamic sealing between the two. In the initial state where the refueling connector components are not connected, the axial length of the sealing bracket (6) extending out of the outer cavity (5-3) is configured to be greater than the axial length of the locking mechanism (10) extending out of the inner cavity (5-6), so that when screwed in, the sealing ring (8) of the sealing bracket contacts and abuts the inner end face of the refueling base body (1) before the locking mechanism protrusion (10-2); after the sealing ring (8) of the sealing bracket abuts the inner end face of the refueling base body (1), the sealing bracket (6) stops rotating with the end face, and the refueling connector body (5) continues to rotate relative to the sealing bracket (6), and the sealing ring (9) of the sealing bracket achieves a rotational dynamic seal between the two.

5. The quick-plug self-sealing oiling connector according to claim 4, characterized in that: The inner core assembly also includes a locking mechanism spring (11). The locking mechanism (10) is a hollow cylinder with its bottom outer edge extending radially outward to form a locking mechanism retaining ring (10-1), which is movably disposed in the inner cavity (5-6) of the refueling connector body (5). The retaining ring (10-1) cooperates with the inner edge of the top of the inner cavity (5-6) to restrict the axial disengagement of the locking mechanism (10). The top end face of the locking mechanism (10) is provided with multiple locking mechanism protrusions (10-2) along the circumferential direction, which are used to interlock with the self-sealing inlet block (1-6) in the refueling base body (1) to achieve circumferential locking. The top center of the locking mechanism (10) has a locking mechanism through hole (10-3). The locking mechanism spring (11) applies an elastic force to the locking mechanism (10) to make it extend out of the inner cavity (5-6), and the elastic force is greater than the frictional force between the locking mechanism protrusion (10-2) and the self-sealing inlet block (1-6) contact surface; The top two sides of the locking mechanism protrusion (10-2) are provided with wedge-shaped guide slopes that are inclined towards the center of the tooth tip. The corresponding mating surface of the self-sealing inlet block (1-6) is provided with a slope that matches the wedge-shaped guide slope, so that when there is any circumferential deviation between the locking mechanism (10) and the self-sealing inlet block (1-6), the circumferential rotational force generated by the slope automatically guides the locking mechanism protrusion (10-2) to insert into the gap of the self-sealing inlet block (1-6).

6. The quick-plug self-sealing oiling connector according to claim 5, characterized in that: The oil outlet core (13) is divided into an oil outlet section (13-1) and a threaded section (13-2) along the axial direction; the radial cross-sectional shape of the oil outlet core section (13-1) matches the radial cross-sectional shape of the locking mechanism through hole (10-3), so that after the oil outlet core (13) is inserted into the locking mechanism through hole (10-3), it is circumferentially linked with the locking mechanism (10) and can slide relative to the axial direction; The threaded section (13-2) is provided with an external thread, which is threadedly engaged with the internal threaded cavity (5-8) of the oil filling connector body (5). During the process of screwing in the oil filling connector body (5), the oil outlet core (13) is driven to move axially relative to the oil filling connector body (5).

7. The quick-plug self-sealing oiling connector according to claim 6, characterized in that: The locking mechanism through hole (10-3) is a cross-shaped hole with a circular center, and the radial cross section of the oil core section (13-1) is a cross shape with the same shape; the internal channel of the oil outlet core (13) is through, and the cooperation between the cross-shaped hole and the cross-shaped cross section realizes the functions of circumferential linkage, axial guidance and central channel oil passage on a single interface. The upper side of the oil core section (13-1) is provided with multiple oil core holes (13-3). After the self-sealing seat cover (2) is opened, the fuel flows through the internal channel of the oil core (13) and the self-sealing seat oil passage hole (1-4) into the fuel tank.

8. The quick-plug self-sealing oiling connector according to claim 7, characterized in that: The top of the oil core segment (13-1) of the oil core (13) is a closed structure. The upper half of the oil core segment (13-1) is provided with multiple oil core holes (13-3). The oil core holes (13-3) are distributed circumferentially on the side wall of the oil core segment (13-1), so that after the self-sealing cover (2) is opened, the fuel enters the internal channel of the oil core (13) radially or obliquely through the oil core holes on the side wall of the oil core segment, thus avoiding the blockage of the oil passage when the self-sealing cover (2) is attached to the top of the oil core (13). The oil outlet core (13) is in the retracted position in the initial state. An oil outlet core head sealing ring (14) is provided between the outer periphery of its top end and the inner wall of the locking mechanism (10) to seal the internal channel of the oil outlet core (13) before the self-sealing seat cover (2) is opened. The cross-section of the oil outlet core head sealing ring (14) is larger at the top and smaller at the bottom. Its radial thickness on the side near the top end of the oil outlet core (13) is greater than the radial thickness on the side away from the top end, so that when the oil outlet core (13) retracts axially relative to the locking mechanism (10) during disassembly, the outer periphery of the oil outlet core head sealing ring (14) slides along the inner wall of the locking mechanism (10). The outer circumferential surface of the self-sealing cover (2) is provided with a self-sealing cover sealing ring groove (2-1) for installing the self-sealing cover sealing ring (3), which is used to seal the self-sealing inlet (1-5) under normal conditions; the cross section of the self-sealing cover sealing ring (3) and / or the sealing bracket sealing ring (8) is convex.

9. A quick-plug self-sealing lubrication method, performed using the quick-plug self-sealing lubrication connector as described in any one of claims 1-8, characterized in that, Includes the following steps: Screw in: Insert the oil filling connector into the threaded cavity (1-2) of the oil filling base and screw it in so that the external thread (5-1) of the oil filling connector body (5) meshes with the internal thread of the threaded cavity (1-2). Move the oil filling connector axially until the sealing ring (8) of the sealing bracket at the top of the sealing bracket (6) abuts against the inner end face of the oil filling base body (1). Seal establishment: Continue to turn the oil filling connector, the sealing bracket spring (7) is compressed, and the sealing bracket (6) is gradually put into the annular outer cavity (5-3) of the oil filling connector body (5). Through the pressing fit between the sealing bracket sealing ring (8) and the end face of the oil filling base body (1), and the fit between the sealing bracket retaining ring (9) and the side wall of the sealing bracket (6), a seal is established between the oil filling connector and the oil filling base. Locking and motion conversion: Continue to turn the oil filling connector, the locking mechanism protrusion (10-2) at the top of the locking mechanism (10) and the self-sealing inlet block (1-6) in the oil filling base body (1) interlock and mesh with each other to achieve circumferential locking. The locking mechanism (10) stops rotating, and the oil outlet core (13) stops rotating accordingly. Self-sealing opening: After the seal is established and the locking mechanism is locked, continue to turn the oil filling connector. Due to the threaded engagement between the threaded section (13-2) of the oil outlet core (13) and the internal threaded cavity (5-8) of the oil filling connector body (5), the oil outlet core (13) is driven to move axially relative to the oil filling connector body (5). The top of the oil outlet core (13) pushes open the self-sealing seat cover (2), compresses the self-sealing seat spring (4), and opens the self-sealing inlet (1-5). Fuel flows into the internal channel of the oil outlet core (13) through the self-sealing seat cavity (1-3), completing the oil circuit connection.

10. The quick-plug self-sealing lubrication method according to claim 9, characterized in that: The disassembly steps also include: reversing the oil filling connector, the oil outlet core (13) moves axially in the opposite direction under the thread drive, and the self-sealing seat cover (2) closes the self-sealing inlet (1-5) first under the action of the self-sealing seat spring (4); continue reversing the screw, the locking mechanism protrusion (10-2) disengages from the self-sealing inlet block (1-6); continue reversing the screw, the sealing bracket (6) resets under the action of the sealing bracket spring (7), and the sealing ring (8) of the sealing bracket disengages from the end face of the oil filling base body (1); continue reversing the screw, and the oil filling connector is completely unscrewed from the oil filling base.

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