Mechanical arm end effector for underwater salvage and use method of mechanical arm end effector

Abstract

The invention relates to a mechanical arm end effector for underwater salvage and a using method thereof, and belongs to the technical field of underwater robots. By integrating a hydraulic-driven rotary drilling assembly and an ejection anchoring mechanism, drilling is completed on an underwater target object at a time, and an anchoring part with a lifting point is implanted; a unique pressure compensation flow channel system is arranged inside, external seawater pressure is automatically balanced through oil pressure, sealing failure is prevented, and operation reliability in a large-depth environment is ensured. The drilling and hoisting device has the functions of drilling and hoisting, a plurality of hoisting points can be continuously established by rapidly replacing the drill bit assembly, and the underwater salvage process is greatly simplified.

Description

Technical Field

[0001] This application relates to the field of underwater robot technology, and in particular to the end effector of a robotic arm for underwater salvage and its usage method. Background Technology

[0002] With the development of underwater operation technology, end effector technology that can be mounted on underwater robotic arms has emerged. This technology can meet various operational needs such as cutting, grasping, and valve opening and closing by changing end tools with different functions, which significantly improves the adaptability and efficiency of underwater operations.

[0003] In related technologies, the end effectors and gripping mechanisms of robotic arms are typically designed to only have grasping functions, suitable for the end joints of general-purpose robotic arms. However, their functions are relatively limited and cannot directly support complex salvage operations such as drilling holes and installing lifting points. In addition, existing technologies also include dedicated lifting point anchoring devices, such as those disclosed in "Application of ROVs and Underwater Tools in Deep-Sea Search and Salvage Operations," but these require pre-reserved lifting points on the salvaged object or pre-drilled holes using other equipment to achieve the lifting function.

[0004] The aforementioned end effector has functional limitations, as it cannot integrate drilling and hoisting point anchoring functions on the same actuator, which restricts the flexibility and response speed of underwater operations, thus making underwater rescue and salvage operations complex. Summary of the Invention

[0005] Based on this, it is necessary to provide an end effector for underwater salvage robotic arms and its usage method to address the above problems. This end effector can simultaneously meet the operational needs of underwater drilling and hoisting, has a high degree of integration, can be directly adapted to underwater robotic arms, and has both underwater drilling and hoisting functions. It can directly enter the hoisting stage, greatly simplifying the underwater salvage operation process.

[0006] An end effector for an underwater salvage robotic arm includes:

[0007] The drill bit assembly is detachably disposed inside the guide flange and is constrained by the guide flange to achieve synchronous rotation;

[0008] A guide flange guides the installation and movement of the drill bit assembly;

[0009] The rotating end cap, piston rod, and integrated cylinder body constitute a hydraulic cylinder structure, and the rotating end cap is fixedly connected to the guide flange.

[0010] The main housing has internal hydraulic channels and compensation chambers;

[0011] The hydraulic motor is connected to the integrated cylinder via a key.

[0012] A flow screw connects the integrated cylinder to the output shaft of the hydraulic motor.

[0013] The integrated cylinder is rotatably disposed inside the main housing and is isolated from the external environment by a rotary sealing structure;

[0014] The first compensation cavity is formed by the main housing, integrated cylinder, flow screw, flow base, flow column and sealing screw;

[0015] A rotary joint is also provided on the flow base for connecting to an external hydraulic circuit;

[0016] The second compensation cavity is formed by the gland, the main housing, and the integrated cylinder.

[0017] In one embodiment, the drill bit assembly includes a drill body, a round head post, and a return post; the drill body is provided with a bearing hole for hoisting and an installation structure for mounting the drill bit; the round head post and the return post form a spring plunger structure for cooperating with the guide flange to achieve circumferential positioning and quick assembly / disassembly.

[0018] In one embodiment, the guide flange is provided with a slant groove, a column groove, and a waist-shaped groove; the slant groove is used to guide the compression of the round headstock; the column groove is used to guide the installation of the drill bit assembly; and the waist-shaped groove is used to receive the ejected round headstock and transmit torque.

[0019] In one embodiment, the main housing is provided with an extension flow channel, a retraction flow channel, a valve pre-flow channel, and a compensation flow channel; the flow base is provided with a first flow channel, a second flow channel, a third flow channel, and a fourth flow channel; the integrated cylinder is provided with a counterbore flow channel, a through-hole flow channel, and a flow ring groove; the flow channels form a hydraulic oil circuit for realizing the oil inlet and return of the hydraulic cylinder and the hydraulic motor, as well as pressure compensation.

[0020] In one embodiment, a one-way valve assembly symmetrically mounted on the main housing is further included; the one-way valve assembly includes a valve seat, a valve core, a plug and an internal valve spring; the valve seat and the valve core are respectively provided with a first damping hole and a second damping hole for providing fluid damping; the one-way valve assembly is used to maintain the pressure of the compensation chamber and prevent seawater intrusion.

[0021] In one embodiment, the flow screw is provided with a compensation ring groove for connecting the rodless chamber of the hydraulic cylinder with the first compensation chamber and providing fluid damping.

[0022] In one embodiment, the inner wall of the gland is interference-fitted with the outer ring of the bearing, and the outer cylindrical surface of the integrated cylinder is interference-fitted with the inner ring of the bearing; the bearing is a cylindrical roller bearing with separable inner and outer rings, and the clearance between the inner and outer rings of the bearing is adjusted by laminations, wherein the laminations are multi-layered separable annular plates with adjustable thickness.

[0023] In one embodiment, the hydraulic motor is a cycloidal motor or a gear motor, and its drain port is directly connected to the first compensation chamber.

[0024] A method for using an end effector of a robotic arm for underwater salvage includes the following steps:

[0025] The end effector is controlled by a robotic arm to bring the drill assembly into contact with the surface of the target object.

[0026] Start the hydraulic motor to drive the drill bit assembly to rotate and perform the hole-opening operation;

[0027] Stop the hydraulic motor, supply oil to the rodless chamber of the hydraulic cylinder, and push the piston rod to extend.

[0028] The drill bit assembly is ejected and anchored in the target object;

[0029] The drill bit assembly is used for hoisting and salvage.

[0030] In one embodiment, after completing one drilling and anchoring step, a new drill bit assembly is inserted into a guide flange using a robotic arm, and the drilling and anchoring steps are repeated to form multiple anchoring points on the target object.

[0031] The aforementioned underwater salvage robotic arm end effector and its usage method feature a drill bit assembly that serves as both a drilling tool and a lifting point. After drilling, the hydraulic power source switches the oil circuit, driving the piston rod to extend and directly insert and anchor the drill bit assembly like a "nail" onto the target object. This process requires no tool replacement, allowing the robotic arm to immediately enter the lifting posture. Furthermore, the guide flange's inclined groove, column groove, and waist-shaped groove, in conjunction with the round-headed column, form a quick-release mechanism, enabling a single actuator to continuously install multiple drill bit assemblies and establish multiple lifting points. This is something that single-function tools cannot achieve, solving the previous problem of having to lower different working tools multiple times (such as lowering the drilling tool first and then the lifting tool), greatly simplifying the salvage process, saving valuable operating time, and reducing operational complexity.

[0032] This application also has the following advantages:

[0033] The first and second compensation chambers of this application are not part of the oil circuit, but rather pressure compensation cavities. They are connected through a compensation flow channel and to a check valve assembly through a pre-valve flow channel. The opening pressure of the check valve assembly is extremely low (not greater than 0.2 bar), ensuring that the oil pressure in the compensation chamber is always slightly higher than the external seawater pressure, but without significantly affecting the main system pressure. This achieves two objectives: first, preventing seawater intrusion, with internal oil seeping outwards in a slight manner, effectively blocking highly corrosive seawater from entering the actuator and protecting precision components; second, balancing pressure, eliminating the pressure difference between the inside and outside of the actuator housing, so that the complex rotary seal and static seal only need to cope with oil pressure, without having to contend with the enormous seawater pressure, greatly reducing the difficulty of seal design and wear; in addition, the hydraulic motor of this application is placed in the compensation chamber, and the oil drain port of the hydraulic motor is directly connected to the first compensation chamber. Its leaked oil can participate in the system's circulating cooling and lubrication, rather than damaging the seal. This design allows for the modification of standard hydraulic motors, reducing costs and technical risks.

[0034] The integrated cylinder body of this application simultaneously serves as the cylinder body of a hydraulic cylinder, the transmission box of a hydraulic motor, and the carrier of a flow channel network (machined with countersunk flow channels, through-hole flow channels, and flow ring grooves), thereby greatly reducing the number of parts, interfaces, and potential leakage points.

[0035] The bearings and laminations in this application are matched, and the bearings with separable inner and outer rings are used. With the addition of multi-layer adjustable laminations, the bearing clearance can be precisely adjusted to ensure that the integrated cylinder can still rotate smoothly under huge radial loads (drilling), thereby improving transmission accuracy and service life. Attached Figure Description

[0036] Figure 1 This is the front view of the end effector of this application.

[0037] Figure 2 for Figure 1 Sectional view of AA.

[0038] Figure 3 for Figure 2 BB section view.

[0039] Figure 4 for Figure 3 A magnified view of a portion of the image.

[0040] Figure 5 for Figure 2 CC section view

[0041] Figure 6 This is a schematic diagram of the drill bit assembly of this application.

[0042] Figure 7 This is an exploded view of the drill bit assembly of this application.

[0043] Figure 8 This is a schematic diagram of the guide flange of this application.

[0044] Figure 9 This is a cross-sectional view of the guide flange of this application.

[0045] Figure 10 This is a schematic diagram of the valve seat structure of this application.

[0046] Figure 11 This is a schematic diagram of the valve core structure of this application.

[0047] Figure 12 This is a schematic diagram of the flow-through base of this application.

[0048] Figure 13 This is a schematic diagram of the integrated cylinder block of this application.

[0049] Figure 14 This is a schematic diagram of the cycloidal motor of this application.

[0050] Figure 15 This is a schematic diagram of the flow column of this application.

[0051] Figure 16 This is a schematic diagram of the initial drilling state of the end effector in one embodiment of this application.

[0052] Figure 17 This is a schematic diagram of the drilling completion state of the end effector in one embodiment of this application.

[0053] Figure 18 This is a hydraulic schematic diagram of the end effector of this application.

[0054] The components include: 1. Drilling assembly; 2. Guide flange; 3. Rotary end cap; 4. Gland; 5. Main housing; 6. Check valve assembly; 7. Flow base; 8. Piston rod; 9. Integrated cylinder body; 10. Bearing; 11. Laminated plate; 12. Flow screw; 13. Hydraulic motor; 14. Flow column; 15. Sealing screw; 16. Rotary joint; 17. First compensation chamber; 18. Second compensation chamber.

[0055] 101. Drill body; 102. Pin; 103. Upper protrusion; 104. Lower protrusion; 105. Small spring; 106. Round head post; 107. Return post;

[0056] 10101, Bearing hole; 10102, Threaded hole; 10103, Rectangular groove; 10104, Drill bit;

[0057] 201. Inclined groove; 202. Column groove; 203. Waist-shaped groove;

[0058] 501. Extended flow channel; 502. Retracted flow channel; 503. First valve downstream flow channel; 504. Second valve downstream flow channel; 505. Valve upstream flow channel; 506. Compensation flow channel;

[0059] 601. Valve seat; 602. Valve core; 60201. Second damping orifice; 603. Plug; 604. Internal valve spring;

[0060] 60101, First damping orifice;

[0061] 701, First flow channel; 702, Second flow channel; 703, Third flow channel; 704, Fourth flow channel;

[0062] 901. Countersunk flow channel; 902. Through-hole flow channel; 903. Flow ring groove;

[0063] 1201. Compensation ring groove;

[0064] 1301, Oil inlet; 1302, Oil return port; 1303, Oil drain port;

[0065] 1401, flow passage; 1402, sealing ring groove. Detailed Implementation

[0066] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0067] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application 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, and therefore should not be construed as a limitation of this application.

[0068] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0069] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0070] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0071] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0072] See Figures 1 to 18 The diagram shows a schematic of an underwater salvage robotic arm end effector and its usage method according to an embodiment of this application.

[0073] This embodiment provides an end effector for an underwater salvage robotic arm, comprising a drill bit assembly 1, a guide flange 2, a rotating end cap 3, a pressure cap 4, a main housing 5, a one-way valve assembly 6, a flow-through base 7, a piston rod 8, an integrated cylinder 9, a bearing 10, a stacked plate 11, a flow-through screw 12, a hydraulic motor 13, a flow-through column 14, a sealing screw 15, and a rotary joint 16.

[0074] In some embodiments, the drill bit assembly 1 is detachably disposed inside the guide flange 2;

[0075] Furthermore, the drill bit assembly 1 specifically includes a drill body 101, a pin 102, an upper protrusion 103, a lower protrusion 104, a small spring 105, a round head post 106, and a return post 107;

[0076] The drill body 101 is machined with a bearing hole 10101 for underwater salvage and hoisting, a threaded hole 10102 for installing a return column 107, a rectangular groove 10103 for housing an upper protrusion 103, a lower protrusion 104 and a small spring 105, and an interface for installing a drill bit 10104.

[0077] Furthermore, the drill bit 10104 can be equipped with twist drills, hole openers, or other structures as needed.

[0078] The upper protrusion 103 and the lower protrusion 104 protrude from the rectangular groove 10103 under the pre-lifting action of the small spring 105, and can be compressed and retracted when subjected to external force. The round head post 106 and the return post 107 together form an internal hexagonal hole type spring plunger, enabling the round head post 106 to have the functions of retraction and ejection, which is the key to realizing the rapid docking and locking of the drill bit assembly 1 and the guide flange 2.

[0079] In some embodiments, the guide flange 2 is fixedly connected to the rotating end cover 3 by screws, and has a slanted groove 201, a column groove 202 and a waist-shaped groove 203 machined on it;

[0080] Furthermore, the slant 201 is used to guide and compress the round head post 106 during the installation of the drill bit assembly 1;

[0081] The groove 202 provides guidance for the axial installation of the drill bit assembly 1;

[0082] The waist-shaped groove 203 provides a space to accommodate the round head column 106 after it pops out, and forms a circumferential constraint through its cooperation with the round head column 106, so as to transmit the rotational torque of the guide flange 2 to the drill bit assembly 1 and achieve synchronous rotation.

[0083] In some embodiments, the rotating end cap 3, the piston rod 8, and the integrated cylinder body 9 together constitute a hydraulic cylinder structure; the rotating end cap 3 and the integrated cylinder body 9 are fixedly connected by screws, and static sealing is achieved between the mating surfaces through two radial sealing structures.

[0084] The large end of the piston rod 8 is clearance-fitted with the integrated cylinder body 9 and adopts a conventional piston sealing structure; its small end is clearance-fitted with the rotating end cover 3 and adopts a piston rod sealing structure; the small end of the piston rod 8 is clearance-fitted with the guide flange 2, and its end abuts against the drilling body 101 of the drill bit assembly 1.

[0085] When oil is supplied to the rodless chamber of the hydraulic cylinder, the piston rod 8 can extend to push the drill assembly 1 out of the guide flange 2.

[0086] In some embodiments, the hydraulic motor 13 is preferably a cycloidal motor or a gear motor, and its output shaft is inserted into the integrated cylinder 9 via a flat key to achieve synchronous torque transmission. A flow-through screw 12 passes through the integrated cylinder 9 and is threadedly connected to the output shaft of the hydraulic motor 13, thereby forming an axial constraint on the integrated cylinder 9 and the hydraulic motor 13.

[0087] In some embodiments, the integrated cylinder 9 is rotatably disposed inside the main housing 5, with a clearance fit between the two, and the internal hydraulic flow channel is isolated from the external compensation chamber environment by a three-stage rotary sealing structure.

[0088] Furthermore, internal flow channels are machined on the integrated cylinder block 9, including countersunk flow channels 901, through-hole flow channels 902, and flow ring grooves 903, for the flow of hydraulic oil.

[0089] In some embodiments, the gland 4 is fixedly mounted on the main housing 5 by screws, and the mating surface is statically sealed by radial sealing.

[0090] The gland 4 and the integrated cylinder 9 are clearance fit, and dynamic sealing is achieved through a rotary sealing structure;

[0091] The bearing 10 is a cylindrical roller bearing with separable inner and outer rings. Its outer ring is interference-fitted into the gland 4, and its inner ring is interference-fitted into the outer cylindrical surface of the integrated cylinder 9.

[0092] The laminate 11 is a multi-layered, adjustable-thickness, separable circular thin sheet. It has a large clearance fit with the integrated cylinder 9, and its two ends abut against the inner ring of the bearing 10 and the main housing 5, respectively. By adjusting the thickness of the laminate 11, the installation clearance between the inner and outer rings of the bearing 10 can be precisely adjusted to ensure the smooth rotation of the integrated cylinder 9.

[0093] In some embodiments, the flow base 7 is mounted on the main housing 5 by screws, with the end faces abutting and end face sealing;

[0094] The two ends of the flow column 14 are inserted into the hydraulic motor 13 and the flow base 7 respectively, both with clearance fit and static sealing achieved through the radial sealing ring (installed in the sealing ring groove 1402 on it).

[0095] Furthermore, the flow column 14 has a flow hole 1401 machined inside for connecting the hydraulic oil circuit;

[0096] Furthermore, the sealing screw 15 is used to connect the hydraulic motor 13 and the flow base 7, and an angle seal structure is adopted between it and the flow base 7;

[0097] Furthermore, four rotary joints 16 are mounted on the flow base 7, serving as interfaces for connecting the entire actuator to an external hydraulic power source.

[0098] In some embodiments, the main housing 5 is internally machined with hydraulic flow channels, including: an extension flow channel 501, a retraction flow channel 502, a first post-valve flow channel 503, a second post-valve flow channel 504, a pre-valve flow channel 505, and a compensation flow channel 506.

[0099] Furthermore, the flow base 7 also has a first flow channel 701, a second flow channel 702, a third flow channel 703, and a fourth flow channel 704 machined inside. These flow channels, together with the flow channels on the integrated cylinder 9, constitute a complete hydraulic system.

[0100] Among them, the first flow channel 701, the first valve downstream flow channel 503, and the extended flow channel 501 are connected to the rodless chamber of the hydraulic cylinder;

[0101] Among them, the second flow channel 702, the second valve downstream flow channel 504, and the retraction flow channel 502 are connected to the rod chamber of the hydraulic cylinder;

[0102] The valve inlet flow channel 505 is connected to the inlet of the check valve assembly 6;

[0103] The compensation channel 506 connects the first compensation cavity 17 and the second compensation cavity 18.

[0104] In some embodiments, two sets of one-way valve assemblies 6 are symmetrically mounted on the main housing 5;

[0105] Furthermore, each one-way valve assembly 6 includes a valve seat 601, a valve core 602, a plug 603, and an internal valve spring 604;

[0106] The valve seat 601 is clearance-fitted with the main housing 5 and has a radial seal, and a first damping hole 60101 is machined on it.

[0107] The valve core 602 is placed inside the valve seat 601 with a small clearance fit, and a second damping hole 60201 is machined on it.

[0108] The first damping orifice 60101 and the second damping orifice 60201 work together to provide fluid damping for the movement of the valve core 602 and reduce impact.

[0109] The plug 603 is threaded to the main housing 5 and uses an angle seal.

[0110] The two ends of the internal spring 604 abut against the valve core 602 and the plug 603 respectively, providing preload force so that the opening pressure of the check valve does not exceed 0.2 bar.

[0111] The one-way valve assembly 6 in this application is used to maintain the pressure in the compensation chamber and prevent seawater backflow.

[0112] In some embodiments, the sealing space formed by the main housing 5, the integrated cylinder 9, the flow screw 12, the flow base 7, the flow column 14 and the sealing screw 15 constitutes the first compensation cavity 17; at the same time, the space formed by the pressure cap 4, the main housing 5 and the integrated cylinder 9 constitutes the second compensation cavity 18.

[0113] Furthermore, the hydraulic motor 13 is entirely placed in the first compensation chamber 17, and its drain port 1303 is directly connected to the chamber;

[0114] There is no seal between the flow screw 12 and the integrated cylinder body 9. The compensation ring groove 1201 machined on it has a damping effect and connects the rodless chamber of the hydraulic cylinder with the first compensation chamber 17.

[0115] This application also provides a method of using and principle of an end effector for underwater salvage robotic arms, as follows:

[0116] Initial installation and positioning: The actuator is operated by the underwater robotic arm to make the drill bit 10104 of the drill bit assembly 1 vertically aligned with the surface of the target object to be salvaged;

[0117] During drilling, the external hydraulic system supplies oil to the inlet 1301 of the hydraulic motor 13 via the rotary joint 16 (oil circuit: fourth flow channel 704 -> third flow channel 703 -> flow hole 1401 of the flow column 14 -> inlet 1301); the hydraulic motor 13 rotates, and the torque is transmitted sequentially to the drill bit assembly 1 through the flat key, integrated cylinder 9, rotating end cover 3, and guide flange 2, thus initiating drilling. Return oil flows from the return port 1302 through the flow hole 1401 and the fourth flow channel 704 back to the drill bit assembly 1.

[0118] After the drilling is completed, the oil supply to the hydraulic motor 13 is stopped; the hydraulic system switches the oil circuit to supply oil to the rodless chamber of the hydraulic cylinder (oil circuit: first flow channel 701 -> first valve downstream flow channel 503 -> extension flow channel 501 -> through hole flow channel 902); the high-pressure oil pushes the piston rod 8 to extend, overcoming the constraint force of the round head column 106 and the waist-shaped groove 203, and completely pushes the drill bit assembly 1 out of the guide flange 2 until its upper protrusion 103 and lower protrusion 104 spring open, firmly anchoring the drill body 101 in the target hole; at this time, the bearing hole 10101 on the drill bit assembly 1 serves as a lifting point and can be directly used to connect the sling for retrieval;

[0119] If multiple lifting points are required, the robotic arm can manipulate the actuator to insert a new drill bit assembly 1 along the inclined groove 201 and column groove 202 of the guide flange 2. The round-headed column 106 is compressed and slides in and pops out at the waist-shaped groove 203.

[0120] Repeating the above steps will allow for continuous and multiple hole drilling and lifting point establishment.

[0121] In addition, the pressure compensation system inside the actuator continues to operate throughout the entire process:

[0122] The high pressure of seawater in the deep-water environment acts on the shell and is transmitted to the second compensation chamber 18 and the first compensation chamber 17 through the compensation channel 506.

[0123] When the oil pressure inside the cavity is lower than the external seawater pressure due to temperature changes or micro-leakage, the seawater pressure will push the valve core 602 of the one-way valve assembly 6 to compress the valve spring 604 and open the valve, so that the oil in the oil tank (through the return pipeline) is replenished to the flow channel 505 before the valve, and then enters the first compensation chamber 17 and the second compensation chamber 18, ensuring that the oil pressure inside the cavity is always basically balanced with the external seawater pressure (slightly higher by about 0.2 bar).

[0124] Pressure compensation not only effectively prevents seawater intrusion, but also allows all static and rotary seals to operate under only the sealing oil pressure, without having to contend with the huge seawater pressure differential, greatly improving sealing reliability and component lifespan. Furthermore, leaking oil from the hydraulic motor 13 is directly discharged into the first compensation chamber 17, and then flows back to the oil tank through the one-way valve assembly 6. When the rodless chamber of the hydraulic cylinder is supplied with oil, the high-pressure oil is isolated by the one-way valve assembly 6. Since the flow screw 12 is not sealing, some hydraulic oil may seep into the first compensation chamber 17, and then flow back to the oil tank through the pre-valve flow channel 505, the one-way valve assembly 6, and the post-valve flow channel 504. When the rod chamber of the hydraulic cylinder is supplied with oil, the high-pressure oil is isolated by the one-way valve assembly 6, without affecting the internal environment of the first compensation chamber 17 and the second compensation chamber 18.

[0125] In summary, this application is compatible with existing general-purpose underwater robotic arms and can simultaneously meet the operational needs of underwater drilling and hoisting. The end effector has universal mechanical and hydraulic interfaces and a high degree of overall integration. With simple modifications, it can be directly adapted to existing five-function and seven-function underwater robotic arms. In addition, considering the complex process of underwater salvage tasks, such as drilling, grinding, hoisting, and lifting, this end effector has the functions of underwater drilling and hoisting, and can directly enter the lifting stage, greatly simplifying the underwater salvage operation process.

[0126] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0127] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An end effector for an underwater salvage robotic arm, characterized in that, include: The drill bit assembly (1) is detachably disposed inside the guide flange (2) and constrained by the guide flange (2) to achieve synchronous rotation; Guide flange (2) guides the installation and movement of the drill bit assembly (1); The rotating end cap (3), piston rod (8) and integrated cylinder body (9) constitute a hydraulic cylinder structure, and the rotating end cap (3) is fixedly connected to the guide flange (2); The main housing (5) has a hydraulic flow channel and a compensation cavity inside; A hydraulic motor (13) is connected to the integrated cylinder (9) via a flat key; A flow screw (12) connects the integrated cylinder (9) to the output shaft of the hydraulic motor (13); The integrated cylinder (9) is rotatably disposed inside the main housing (5) and is isolated from the external environment by a rotary sealing structure; The first compensation cavity (17) is formed by the main housing (5), integrated cylinder (9), flow screw (12), flow base (7), flow column (14) and sealing screw (15); A rotary joint (16) is also provided on the flow base (7) for connecting to an external hydraulic circuit; The second compensation cavity (18) is formed by the gland (4), the main housing (5) and the integrated cylinder (9).

2. The underwater salvage robotic arm end effector according to claim 1, characterized in that, The drill bit assembly (1) includes a drill body (101), a round head post (106), and a return post (107); The drilling body (101) is provided with a bearing hole (10101) for hoisting and an installation structure for installing the drill bit (10104); The round-headed column (106) and the return column (107) constitute a spring plunger structure, which is used to cooperate with the guide flange (2) to achieve circumferential positioning and quick assembly / disassembly.

3. The underwater salvage robotic arm end effector according to claim 2, characterized in that, The guide flange (2) is provided with a slanted groove (201), a column groove (202), and a waist-shaped groove (203); The inclined groove (201) is used to guide the compression of the round-headed column (106); The groove (202) is used to guide the installation of the drill bit assembly (1); The waist-shaped groove (203) is used to receive the ejected round-headed column (106) and transmit torque.

4. The end effector for underwater salvage robotic arms according to claim 1, characterized in that: The main housing (5) is provided with an extension flow channel (501), a retraction flow channel (502), a valve inlet flow channel (505), and a compensation flow channel (506); The flow base (7) is provided with a first flow channel (701), a second flow channel (702), a third flow channel (703) and a fourth flow channel (704); The integrated cylinder body (9) is provided with a countersunk flow channel (901), a through flow channel (902), and a flow ring groove (903); The hydraulic circuit is formed by the flow channel to realize the oil inlet and return of the hydraulic cylinder and hydraulic motor (13), as well as pressure compensation.

5. The underwater salvage robotic arm end effector according to claim 1, characterized in that, It also includes a one-way valve assembly (6) symmetrically mounted on the main housing (5); The one-way valve assembly (6) includes a valve seat (601), a valve core (602), a plug (603), and an internal valve spring (604); The valve seat (601) and the valve core (602) are respectively provided with a first damping hole (60101) and a second damping hole (60201) to provide fluid damping; The one-way valve assembly (6) is used to maintain the pressure in the compensation chamber and prevent seawater intrusion.

6. The underwater salvage robotic arm end effector according to claim 1, characterized in that, The flow screw (12) is provided with a compensation ring groove (1201) for connecting the rodless chamber of the hydraulic cylinder with the first compensation chamber (17) and providing fluid damping.

7. The underwater salvage robotic arm end effector according to claim 1, characterized in that, The inner wall of the pressure cap (4) is interference-fitted with the outer ring of the bearing (10), and the outer cylindrical surface of the integrated cylinder body (9) is interference-fitted with the inner ring of the bearing (10). The bearing (10) is a cylindrical roller bearing with separable inner and outer rings, and the gap between the inner and outer rings of the bearing (10) is adjusted by a stack (11), which is a multi-layered, adjustable-thickness separable ring.

8. The underwater salvage robotic arm end effector according to claim 1, characterized in that, The hydraulic motor (13) is a cycloidal motor or a gear motor, and its drain port (1303) is directly connected to the first compensation chamber (17).

9. A method of using the end effector of an underwater salvage robotic arm as described in any one of claims 1-8, characterized in that, Includes the following steps: The drill assembly (1) is brought into contact with the surface of the target object by controlling the end effector with the robotic arm; Start the hydraulic motor (13) to drive the drill bit assembly (1) to rotate and perform the hole opening operation; Stop the hydraulic motor (13), supply oil to the rodless chamber of the hydraulic cylinder, and push the piston rod (8) to extend. The drill assembly (1) is ejected and anchored in the target object; The retrieval is carried out through the lifting hole provided on the drill bit assembly (1).

10. The method of using the end effector of the underwater salvage robotic arm according to claim 9, characterized in that, It also includes, after completing one drilling and lifting point installation, using a robotic arm to install a new drill bit assembly (1) into a guide flange (2), repeating the drilling and anchoring steps to form multiple lifting points on the target object.

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