Multifunctional rotary excavator accessory

Abstract

The invention discloses a multifunctional rotary excavator accessory which comprises a connecting base, a rotary driving mechanism and a hydraulic clamping mechanism. The connecting base is used for being detachably connected with the front end of an excavator big arm. The rotary driving mechanism is mounted below the connecting base; the hydraulic clamping mechanism comprises a fixing base, a pair of clamping arms, a hydraulic oil cylinder installation base and hydraulic oil cylinders symmetrically hinged to the two sides of the installation base. The piston rod ends of the two oil cylinders are hinged to the middles of the clamping arms on the corresponding sides through third pin shafts respectively. A gripper assembly is installed at the free end of the clamping arm, the gripper assembly comprises a clamping panel and a hidden hook hinged to the interior of the installation notch through a fourth pin shaft, and the hidden hook is provided with a limiting hole and is matched with a positioning through hole in the side face of the clamping arm through a plug pin to achieve mechanical locking of the working posture and the folding posture. According to the invention, stable grabbing of multiple types of materials and hooking of the balancing weight to cooperate with stacking test operation can be realized, and the robot has the characteristics of flexible rotation, high universality, manpower release, economy, safety and reliability.

Description

Technical Field

[0001] This invention relates to the field of engineering machinery attachments, specifically to a multi-functional rotary excavator attachment. Background Technology

[0002] Excavators, as core construction equipment in the engineering and construction field, can flexibly achieve diversified operation functions such as digging, crushing, grabbing, and hooking by changing different attachments. Among them, gripper attachments are one of their commonly used tools. In scenarios such as building construction, bridge construction, foundation load testing, and municipal engineering, gripper attachments are widely used to grab materials such as I-beams, H-beams, paving steel plates, Larssen sheet piles, timber, and cement counterweights.

[0003] Currently, conventional excavator grab attachments on the market have the following technical defects:

[0004] 1. Limited Rotation Function and Insufficient Flexibility: Most existing excavator grabbers' rotation mechanisms can only achieve a small range of oscillation or rotation within a limited angle. When the work space is narrow or the material placement is variable, operators need to frequently adjust the excavator's overall position to achieve alignment, resulting in low work efficiency and difficulty in meeting the demands of high-precision operations such as precise loading and equipment alignment. Furthermore, most existing rotation mechanisms lack reliable self-locking functionality. During heavy-duty grabbing or loading operations, the grabber is prone to unexpected rotation due to external forces, posing a safety hazard.

[0005] 2. The clamping mechanism is poorly designed, resulting in uncoordinated opening and closing movements. Existing grippers often use a single hydraulic cylinder paired with a linkage or gear synchronization mechanism to drive the left and right clamping arms. This leads to complex structures, high manufacturing costs, and poor synchronization between the left and right clamping arms. Some grippers directly drive the clamping arms with hydraulic cylinders, lacking a reasonable lever-type hinge structure. This results in unstable clamping force output, making it difficult to flexibly adjust the clamping force according to the material weight. Insufficient clamping force is common when gripping heavy materials, while excessive clamping force can cause deformation or damage to lightweight materials. Furthermore, the existing hinge connection between the clamping arm and the fixed base is mostly a direct shaft connection, lacking an optimized force transmission path. Under long-term heavy-load operation, the hinge points are prone to wear and loosening, affecting service life.

[0006] 3. Limited gripper functionality, unable to adapt to multiple material types: Most existing gripper components are fixed structures, designed only for a single material type. For example, grippers specifically for steel profiles cannot stably grip paving steel plates or timber, while grippers specifically for steel plates struggle to hold I-beams or Larssen sheet piles. When multiple materials need to be handled on construction sites, operators either frequently change gripper gloves or force operations using incompatible grippers, leading to material slippage, insecure gripping, surface damage, or even accidents caused by material falling and injuring personnel. While some grippers have simple anti-slip teeth, they lack specialized adaptation structures for different material shapes (such as the flanges of steel profiles, the flat surfaces of steel plates, and the round surfaces of timber), resulting in extremely poor versatility. Furthermore, most existing grippers are fixed and non-adjustable, unable to switch between working and non-working states. In confined spaces, protruding, concealed hooks can easily interfere with surrounding obstacles, limiting the gripper's applicability. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a multi-functional rotary excavator attachment that overcomes these limitations. It enables stable gripping and heavy-load loading tests of various materials, including I-beams, H-beams, paving steel plates, Larssen sheet piles, and timber. By incorporating a concealed hook, it can securely grab specialized cement counterweights when extended, precisely adapting to the loading operations required for single-pile bearing capacity tests and plate load tests in foundations. When retracted, it is completely hidden, without affecting conventional gripping functions. This not only optimizes personnel allocation and reduces labor costs but also significantly improves operational safety, providing an efficient, economical, and reliable integrated solution for engineering construction.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A multi-functional rotary excavator attachment includes a connecting base, a rotary drive mechanism, and a hydraulic clamping mechanism. The connecting base is used to form a detachable fixed connection with the front end of the excavator's boom. The rotary drive mechanism is installed below the connecting base and is used to drive the entire hydraulic clamping mechanism to achieve 360-degree stepless continuous rotation in the horizontal plane.

[0010] The hydraulic clamping mechanism is connected below the rotary drive mechanism. The hydraulic clamping mechanism includes a fixed base, which is fixedly installed on the rotary output component of the rotary drive mechanism. A pair of clamping arms are symmetrically arranged on both sides below the fixed base. One end of each clamping arm is hinged to the fixed base via a first pin. A hydraulic cylinder mounting base is fixedly welded to the middle of the fixed base. A pair of hydraulic cylinders are symmetrically arranged on both sides of the hydraulic cylinder mounting base. The hydraulic cylinders are located above the clamping arms. The cylinder bodies of the two hydraulic cylinders are respectively hinged to the hydraulic cylinder mounting base via second pins. The piston rods of the two hydraulic cylinders are respectively hinged to the middle of the corresponding clamping arm via third pins. A gripper assembly is installed on the free end of each clamping arm.

[0011] Preferably, the gripper assembly includes a clamping panel and a hidden hook. The clamping panel is fixedly welded to the free end of the clamping arm, and the inner side of the clamping panel protrudes from the free end of the clamping arm to form a planar clamping part for clamping the workpiece.

[0012] The clamping arm and the clamping panel have through mounting slots on their inner sides. The inner side and bottom of the mounting slots are open. The mounting slots are hinged to one end of a hidden hook via a fourth pin. The other end of the hidden hook is bent to form a hook-shaped structure. When the hidden hook rotates around the fourth pin to the working state, the hook-shaped structure of the hidden hook extends out of the bottom of the clamping panel, and the hook tip faces the inner side of the clamping arm.

[0013] Preferably, the concealed hook has a limiting hole in the middle, and the clamping arm has two positioning through holes on its side that extend along the thickness direction of the clamping arm. The two positioning through holes are symmetrically arranged on both sides of the fourth pin. The limiting hole and any of the positioning through holes are engaged by a pin. When the concealed hook is in the extreme position of being fully extended or fully retracted, the pin is inserted into the limiting hole and the corresponding positioning through hole to achieve mechanical positioning and locking of the concealed hook in the two working postures.

[0014] Preferably, the inner surface of the hook groove of the concealed hook is provided with anti-slip and wear-resistant serrations.

[0015] Preferably, the hidden hook has a steel adapter slot inside the hook groove.

[0016] Preferably, the outer side of the planar clamping part of the clamping panel is provided with a chamfered transition, and a rubber anti-slip pad is fixedly installed on the upper surface of the planar clamping part of the clamping panel.

[0017] Preferably, the rotary drive mechanism includes a hydraulic motor and a slewing bearing. The outer ring of the slewing bearing is fixedly connected to the lower end face of the connecting base, and the inner ring of the slewing bearing is fixedly connected to the upper end face of the fixed base. The housing of the hydraulic motor is fixedly mounted on the connecting base or the outer ring of the slewing bearing. A transmission gear is coaxially fixedly mounted on the output shaft of the hydraulic motor. The transmission gear meshes with the gear ring of the inner ring of the slewing bearing. The hydraulic motor drives the inner ring and outer ring of the slewing bearing to rotate relative to each other through the transmission gear, thereby driving the hydraulic clamping mechanism to achieve 360-degree continuous rotation in the horizontal plane relative to the connecting base.

[0018] Preferably, the slewing bearing is a double-row ball bearing heavy-duty slewing bearing, the outer ring of the slewing bearing is fixedly connected to the connecting base by a set of high-strength bolts, and the inner ring of the slewing bearing is fixedly connected to the upper end plate of the fixed base by a set of high-strength bolts; the hydraulic motor is a high-torque low-speed hydraulic motor, and the housing of the hydraulic motor is mounted on the lower surface of the connecting base through a flange.

[0019] Preferably, the rotary drive mechanism also integrates a rotary self-locking device, which is a hydraulic lock installed on the rotary control oil circuit of the rotary drive mechanism. When the hydraulic motor stops supplying oil, the hydraulic lock cuts off the oil circuit to lock the output shaft of the hydraulic motor, thereby achieving rotary self-locking.

[0020] Preferably, it further includes a heavy-duty reinforcement structure, which includes reinforcing ribs disposed on the outer or inner side of the gripping arm, a slewing bearing reinforcement seat disposed between the rotary drive mechanism and the connecting base or hydraulic gripping mechanism, and a load-bearing pad disposed on the force-bearing surface of the gripper assembly.

[0021] This invention provides a multi-functional rotary excavator attachment. It offers the following advantages: by incorporating a rotary drive mechanism, the entire hydraulic clamping mechanism can achieve 360-degree continuous stepless rotation in the horizontal plane. Compared to existing grippers that can only achieve a small range of oscillation, this invention can complete material alignment and stacking at any angle without moving the entire excavator, making it particularly suitable for confined construction spaces, complex storage yards, and multi-directional material transfer scenarios. The hydraulic clamping mechanism adopts a design with symmetrically arranged dual hydraulic cylinders and lever-type hinged transmission. Two independent cylinders drive the clamping arms on both sides respectively. The symmetrical arrangement and hydraulic system diversion ensure synchronous opening and closing, avoiding synchronization deviations caused by gear wear or connecting rod deformation.

[0022] The gripper assembly integrates a clamping panel and a concealed hook, featuring a switchable dual-position mechanical positioning structure for adaptability to various materials. The inner edge of the clamping panel protrudes from the free end of the clamping arm, forming a flat clamping section suitable for gripping flat surfaces such as paving steel plates. The concealed hook is suitable for hooking H-beams, H-beams, Larssen sheet piles, timber, and cement counterweights from the bottom. The concealed hook is hinged to the mounting slot via a fourth pin. A limiting hole is located in the center of the concealed hook, and two symmetrically distributed positioning through holes on either side of the fourth pin are located on the side of the clamping arm. The engagement of the pin with the limiting hole enables mechanical positioning and locking of the concealed hook in both extended and retracted positions. In its extended position, the hook-shaped structure of the concealed hook extends from below the clamping panel, allowing materials to be hooked from the bottom. In its retracted position, the concealed hook is completely retracted into the mounting slot, not protruding beyond the lower edge of the clamping panel. This design is suitable for scenarios requiring only flat clamping or for unloaded movement and obstacle avoidance in confined spaces. This design allows the attachment to handle various materials such as structural steel, steel plates, timber, and counterweights without changing the gripper, significantly improving the equipment's versatility and operational efficiency, and solving the pain points of existing grippers that are limited in function and require frequent attachment changes. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in this invention or the prior art, the accompanying drawings used in the description of the prior art will be briefly introduced below.

[0024] Figure 1 A schematic diagram of the structure of this invention;

[0025] Explanation of the labels in the diagram:

[0026] 1. Connecting base; 2. Rotary drive mechanism; 3. Hydraulic clamping mechanism; 4. Gripper assembly; 31. Fixed seat; 32. Clamping arm; 33. Hydraulic cylinder mounting seat; 34. Hydraulic cylinder; 35. First pin; 36. Second pin; 37. Third pin; 41. Clamping panel; 42. Concealed hook; 43. Mounting slot; 44. Insert pin; 45. Fourth pin. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0028] Example 1, as Figure 1As shown, a multi-functional rotary excavator attachment includes a connecting base 1, a rotary drive mechanism 2, and a hydraulic clamping mechanism 3. The connecting base 1 is used to form a detachable fixed connection with the front end of the excavator's boom. In this embodiment, the connecting base 1 is welded from Q690 high-strength steel plate, and its upper end face is provided with a flange. The flange has eight evenly distributed bolt connection holes for quick docking and disassembly with the flange at the front end of the excavator's boom using high-strength bolts. The structure of this connecting base 1 is compatible with mainstream 20-30 ton excavator mainframes, and installation and disassembly are convenient.

[0029] The rotary drive mechanism 2 is installed below the connecting base 1 and is used to drive the entire hydraulic clamping mechanism 3 to achieve 360-degree stepless continuous rotation in the horizontal plane.

[0030] The hydraulic clamping mechanism 3 is connected below the rotary drive mechanism 2. The hydraulic clamping mechanism 3 includes a fixed base 31, which is fixedly installed on the rotary output component of the rotary drive mechanism 2. A pair of clamping arms 32 are symmetrically arranged on both sides below the fixed base 31. The clamping arms 32 are made of Q550 high-strength steel plate. One end of the clamping arm 32 (i.e. the fixed end) is hinged to the fixed base 31 through the first pin 35, so that the clamping arm 32 can swing around the first pin 35 in the vertical plane. A hydraulic cylinder mounting base 33 is fixedly welded to the middle of the fixed base 31. A pair of hydraulic cylinders 34 are symmetrically arranged on both sides of the hydraulic cylinder mounting base 33. The hydraulic cylinders 34 are located above the clamping arms 32. The cylinder bodies of the two hydraulic cylinders 34 are respectively hinged to the hydraulic cylinder mounting base 33 through the second pin 36. The piston rods of the two hydraulic cylinders 34 are respectively hinged to the middle of the corresponding clamping arms 32 through the third pin 37. The above-mentioned hinge structure forms a lever-type transmission relationship: when the piston rod of the hydraulic cylinder 34 retracts, it pulls the middle of the clamping arm 32 to swing outward, and the two clamping arms 32 open; when the piston rod of the hydraulic cylinder 34 extends, it pushes the middle of the clamping arm 32 to swing inward around the first pin 35, and the two clamping arms 32 close, thereby realizing the clamping of materials. In this embodiment, the hydraulic cylinder 34 is a double-acting hydraulic cylinder with a cylinder diameter of 120mm, a stroke of 300mm, and a maximum clamping force of 25 tons. The clamping force can be infinitely adjusted by the hydraulic valve group of the excavator host, adapting to different clamping needs from light wood to heavy cement counterweights.

[0031] A gripper assembly 4 is installed at the free end of the gripping arm 32. The gripper assembly 4 includes a gripping panel 41 and a hidden hook 42. The gripping panel 41 is fixedly welded to the free end of the gripping arm 32. The inner side of the gripping panel 41 protrudes from the free end of the gripping arm 32 to form a planar gripping part for gripping the workpiece. This planar gripping part is used to fit and grip materials with flat surfaces, such as paving steel plates. The inner sides of the clamping arm 32 and the clamping panel 41 are provided with through mounting slots 43. The inner side and the bottom of the mounting slots 43 are open. The mounting slots 43 are hinged to one end of the hidden hook 42 through the fourth pin 45. The other end of the hidden hook 42 is bent to form a hook-shaped structure. When the hidden hook 42 rotates around the fourth pin 45 to the working state, the hook-shaped structure of the hidden hook 42 extends out of the bottom of the clamping panel 41, and the hook tip faces the inner side of the clamping arm 32, for hooking materials such as steel or cement counterweights from the bottom.

[0032] This embodiment also provides a mechanical positioning structure for switching between two working postures of the concealed hook 42. The concealed hook 42 has a limiting hole in the middle, and the clamping arm 32 has two positioning through holes on its side that extend along the thickness direction of the clamping arm. The two positioning through holes are symmetrically arranged on both sides of the fourth pin 45. The limiting hole and either positioning through hole are engaged by a pin 44. Specifically, when the concealed hook 42 needs to be unfolded to the working state, the concealed hook 42 is rotated so that its hook-shaped structure extends out from under the clamping panel 41. At this time, the limiting hole on the concealed hook 42 is aligned with the positioning through hole located on one side (such as the front side) of the fourth pin 45. Inserting the pin 44 will lock the concealed hook 42 in the working posture. When the concealed hook 42 needs to be retracted to a non-working state (such as when using the clamping panel 41 or transporting under no-load conditions to avoid interference between the concealed hook and obstacles), rotate the concealed hook 42 in the reverse direction so that its hook-shaped structure retracts into the mounting slot 43. At this time, the limiting hole aligns with the positioning through hole located on the other side (such as the rear side) of the fourth pin 45. Inserting the pin 44 will lock the concealed hook 42 in the retracted position. This mechanical positioning structure has the advantages of simple structure, convenient operation, and reliable locking. It can quickly switch the state of the concealed hook according to the needs of operation, expanding the working condition adaptability of the gripper.

[0033] Working principle:

[0034] In subsequent use, the flange at the upper end of the connecting base 1 is fixedly connected to the flange at the front end of the excavator boom using high-strength bolts, thus achieving mechanical docking between the attachment and the excavator main unit. Simultaneously, the hydraulic control system of the attachment is connected to the hydraulic lines of the excavator main unit, with the excavator main unit providing the hydraulic power source. The operating handles in the excavator cab independently control the rotary drive mechanism 2 and the hydraulic clamping mechanism 3 by controlling the direction, flow, and pressure of the hydraulic oil lines.

[0035] When the operator supplies oil to the rotary control oil circuit, the rotary drive mechanism 2 is activated, thereby driving the entire hydraulic clamping mechanism 3 and the gripper assembly 4 below it to rotate continuously in the horizontal plane relative to the connecting base 1. By controlling the oil supply direction and flow rate, stepless speed regulation rotation in clockwise or counterclockwise directions can be achieved, with no limitation on the rotation angle, achieving a continuous 360-degree rotation effect.

[0036] Once the gripper rotates to the target angle, the operator switches to the clamping control hydraulic circuit. When oil is supplied to the rod chamber of the hydraulic cylinder 34, the piston rod retracts, pulling the middle of the clamping arm 32 to swing outward. Because the rear end of the clamping arm 32 is constrained by the first pin 35, its front end (free end) opens outward, the two clamping arms 32 separate, and the gripper is in a released state. Conversely, when oil is supplied to the rodless chamber of the hydraulic cylinder 34, the piston rod extends, pushing the middle of the clamping arm 32 to swing inward, its front end closes inward, the two clamping arms 32 come together, and the gripper is in a clamping state. By adjusting the pressure of the hydraulic oil, the clamping force can be steplessly controlled, achieving flexible clamping of materials of different weights and hardnesses, avoiding material deformation due to excessive clamping force or slippage due to insufficient clamping force.

[0037] The gripper assembly 4 consists of a clamping panel 41 and a hidden hook 42 forming a composite gripping interface, which can select different gripping methods according to the material shape.

[0038] (I) Working Principle of Planar Clamping: When gripping materials with flat surfaces such as paving steel plates, the main reliance is on the planar clamping part protruding from the inner side of the clamping panel 41. At this time, the hidden hook 42 can be rotated around the fourth pin 45 to a retracted position to avoid the hidden hook extending and causing interference or scratches to the steel plate. When the left and right clamping arms 32 are closed, the planar clamping parts on both sides fit against the edges of the steel plate, so that the edges of the steel plate are evenly clamped on the upper surface of the planar clamping parts, thereby achieving high-precision and high-stability planar clamping. Afterwards, the steel plate is transferred to the target position, and the clamping arms 32 are opened to release the steel plate.

[0039] (II) Hook-type gripping working principle: When gripping I-beams, H-beams, Larssen sheet piles, timber, or cement counterweights, the concealed hook 42 can be rotated around the fourth pin 45 to the working state and locked by the pin 44. Thus, when the clamping arm 32 is closed, the hook-shaped structure of the concealed hook 42 can effectively hook the flange, edge, or lifting boss of the material, while the clamping panel 41 provides auxiliary limiting from the side, forming a dual gripping mode of "bottom support + side limiting", effectively preventing the material from slipping during the transfer process.

[0040] (III) Working Principle of Hidden Hook with Dual-Position Switching: To adapt to the needs of different working spaces, the hidden hook 42 is designed with two postures: extended and retracted. When it is necessary to grab materials that need to be hooked from the bottom or to conduct a stacking test, rotate the hidden hook 42 so that its hook-shaped structure extends out from under the clamping panel 41, and insert the pin 44 into the limiting hole and the positioning through hole located in front of the fourth pin shaft 45 to lock it in the working posture. When working in a confined space, moving without load, or only needing to clamp on a flat surface, rotate the hidden hook 42 in the opposite direction so that its hook-shaped structure retracts into the mounting slot 43, and insert the pin 44 into the positioning through hole on the rear side to lock it in the retracted posture, thus avoiding interference between the hidden hook and obstacles.

[0041] After the operation is completed, the concealed hook 42 can be switched to the retracted position and locked by inserting the pin 44 to protect the concealed hook and reduce the storage size. Then rotate the handle to rotate the gripper assembly to the preset zero position (such as facing forward) for quick use next time. If it is necessary to remove this attachment from the excavator, first turn off the excavator engine, depressurize the hydraulic system, disconnect the hydraulic quick coupling, remove the high-strength bolts on the flange of the connecting base 1, and lift the attachment to the storage rack.

[0042] This invention utilizes a rotary drive mechanism 2 to enable the entire hydraulic clamping mechanism 3 to achieve 360-degree stepless continuous rotation in the horizontal plane. Compared to existing grippers that can only achieve a small range of oscillation (e.g., 0-90°), this invention can complete material alignment and stacking at any angle without moving the entire excavator, making it particularly suitable for confined construction spaces, complex storage yards, and multi-directional material transfer scenarios. The hydraulic clamping mechanism 3 adopts a design with symmetrically arranged dual hydraulic cylinders 34 and lever-type hinged transmission. The two independent cylinders drive the clamping arms on both sides respectively. The symmetrical arrangement and hydraulic system diversion ensure synchronous opening and closing, avoiding synchronization deviations caused by gear wear or connecting rod deformation.

[0043] The gripper assembly 4 integrates two functional components: a clamping panel 41 and a concealed hook 42. It features a switchable dual-station mechanical positioning structure, enabling one-machine adaptation to various materials. The inner side of the clamping panel 41 protrudes from the free end of the clamping arm, forming a flat clamping section suitable for clamping materials on flat surfaces such as paving steel plates. The concealed hook 42 is suitable for hooking I-beams, H-beams, Larssen sheet piles, timber, and cement counterweights from the bottom. The concealed hook 42 is hinged to the mounting slot 43 via a fourth pin 45. A limiting hole is provided in the center of the concealed hook, and two symmetrically distributed positioning through holes are provided on the side of the clamping arm on both sides of the fourth pin. Through the cooperation of the pin 44 and the limiting hole, the concealed hook achieves mechanical positioning and locking in both extended (working) and retracted (non-working) postures. In its extended position, the hook-shaped structure of the concealed hook extends below the clamping panel, allowing materials to be hooked from the bottom. In its retracted position, the concealed hook is completely retracted into the mounting slot, not protruding beyond the lower edge of the clamping panel. This design is suitable for scenarios requiring only flat clamping (such as gripping paving steel plates) or for unloaded movement and obstacle avoidance in confined spaces. This design allows the attachment to handle various materials such as structural steel, steel plates, timber, and counterweights without changing the gripper, significantly improving the equipment's versatility and operational efficiency, and solving the pain points of existing grippers that are limited in function and require frequent attachment changes.

[0044] The upper surface of the connecting base 1 is equipped with a flange with multiple evenly distributed bolt holes. High-strength bolts allow for quick docking and disassembly with the flange at the front of the excavator boom, making it compatible with mainstream 20-30 ton excavator mainframes without requiring any modifications. The hidden hook 42 of the gripper assembly 4 uses a pin-positioning structure, allowing for easy switching of working postures without special tools. Replacement of the gripper can also be quickly achieved through a detachable connection (such as bolt connection). Furthermore, all hinge points use pin connections, facilitating easy replacement after wear and reducing maintenance costs.

[0045] In Example 2, as a further preferred embodiment of Example 1, the inner surface of the hook groove of the concealed hook 42 is provided with anti-slip and wear-resistant serrations. The hook groove of the concealed hook 42 is a key part that directly contacts and bears the weight of materials (such as I-beams, H-beams, Larssen sheet piles, timber, cement counterweights, etc.). By setting anti-slip and wear-resistant serrations on the inner surface of the hook groove, the coefficient of friction between the hook groove and the material surface is increased, forming a microscopic "biting" effect. This effectively suppresses the tendency of the material to slide in the hook groove, making the contact state between the material and the concealed hook more stable. Thus, when dealing with steel materials, since the surface of steel is usually relatively smooth and may have oil stains or rust, the anti-slip serrations can pierce or embed in the small unevenness of the steel surface, effectively preventing the steel from sliding or laterally dislodging along the length of the hook groove during gripping and transfer. When dealing with timber materials, the surface of timber is relatively rough, but round logs are prone to rolling in the hook groove. The serrated structure can be embedded in the surface of the wood, creating additional resistance and preventing the wood from rotating or axially shifting within the groove.

[0046] In Example 3, as a further preferred embodiment of Example 1, the concealed hook 42 has a steel profile adaptation slot within its hook groove. Its shape and size are configured to match the profile of the flange or web of the target steel profile (e.g., the slot width corresponds to the flange thickness of the I-beam, and the slot depth corresponds to the flange extension length). When the concealed hook picks up the steel profile from the bottom, the flange or web of the steel profile can naturally embed into the slot, forming a shape-fitting positioning fit. This ensures that the steel profile is constrained in the predetermined position by the slot and will not tilt or twist laterally due to uneven clamping force or shift in the material's center of gravity, ensuring that the steel profile always remains horizontal or in its designed posture, facilitating subsequent stacking or installation. This allows the steel profile to automatically center within the concealed hook, eliminating the need for operators to repeatedly adjust the gripper angle or excavator position, significantly reducing the difficulty and time required for alignment.

[0047] As a preferred implementation, the steel profile adapter slot can be designed with an adjustable width structure (e.g., by adding or removing shims, sliding adjustment blocks, or using multiple slot sections of different widths). This allows the same concealed hook to be adapted to different specifications of I-beams, H-beams, and Larssen sheet piles without the need to change the gripper or attachments.

[0048] In Example 4, as a further preferred embodiment of Example 1, the outer side of the planar clamping portion of the clamping panel 41 is provided with a beveled transition chamfer, and a rubber anti-slip pad is fixedly installed on the upper surface of the planar clamping portion of the clamping panel 41. By setting the beveled transition chamfer, the right-angled edge is transformed into a smooth beveled transition. Thus, when gripping the paving steel plate, the beveled transition chamfer can guide the edge of the steel plate to slide naturally into the clamping area, avoiding the steel plate from lifting, shifting, or being damaged due to right-angle collision. At the same time, the beveled chamfer and the edge of the steel plate form a pre-guiding effect, completing the initial positioning before the clamping force is fully applied, improving the success rate of gripping on the first attempt.

[0049] Furthermore, the surface of paving steel plates is typically smooth and may be contaminated with dirt, oil, or water. The coefficient of friction between the metal clamping panel and the steel plate is low (approximately 0.2-0.3 under dry friction conditions). Under tilting, vibration, or impact conditions, the steel plate can easily slip off the clamping panels, causing safety accidents. By fixing a rubber anti-slip pad to the upper surface of the planar clamping part of the clamping panel 41, the rubber anti-slip pad, made of a high-friction coefficient rubber material (such as nitrile rubber or polyurethane), achieves a friction coefficient of 0.6-0.8 or higher with the steel plate, increasing static friction by 2-3 times and effectively preventing the steel plate from slipping during clamping. Even in wet or oily environments, the rubber anti-slip pad maintains good gripping ability. Moreover, the rubber anti-slip pad has good flexibility and compressibility, and can undergo local elastic deformation under clamping pressure, adaptively conforming to the surface contour of the steel plate. Even with slight deformation of the steel plate, it ensures a large actual contact area, achieving uniform and stable clamping.

[0050] In Example 5, as a further preferred embodiment of Example 1, the rotary drive mechanism 2 includes a hydraulic motor and a slewing bearing. The outer ring of the slewing bearing is fixedly connected to the lower end face of the connecting base 1, and the inner ring of the slewing bearing is fixedly connected to the upper end face of the fixed seat 31. The housing of the hydraulic motor is fixedly mounted on the connecting base 1 or the outer ring of the slewing bearing. A transmission gear is coaxially fixedly mounted on the output shaft of the hydraulic motor. The transmission gear meshes with the gear ring of the inner ring of the slewing bearing. The hydraulic motor drives the inner ring and the outer ring of the slewing bearing to rotate relative to each other through the transmission gear, thereby driving the hydraulic clamping mechanism 3 to achieve 360-degree continuous rotation in the horizontal plane relative to the connecting base 1.

[0051] The slewing bearing adopts a double-row ball heavy-duty slewing bearing. The outer ring of the slewing bearing is fixedly connected to the connecting base 1 by a high-strength bolt group, and the inner ring of the slewing bearing is fixedly connected to the upper end plate of the fixed seat 31 by a high-strength bolt group. The hydraulic motor is a high-torque low-speed hydraulic motor, and the housing of the hydraulic motor is installed on the lower surface of the connecting base 1 through a flange.

[0052] The hydraulic motor drives the transmission gear to mesh with the inner ring gear of the slewing bearing, causing the inner ring to rotate relative to the outer ring. Since the inner ring is fixedly connected to the fixed seat 31 and the outer ring is fixedly connected to the connecting base 1, the hydraulic clamping mechanism 3 can achieve 360-degree stepless continuous rotation relative to the connecting base 1 (i.e., the excavator boom) in the horizontal plane. Compared to existing grippers that can only swing within a small range, this design can complete material alignment, stacking, and transfer at any angle without moving the entire excavator. It is particularly suitable for confined construction spaces, complex stockpiles, and multi-directional material grabbing scenarios, significantly improving operational flexibility and efficiency. Furthermore, by adopting a double-row ball bearing heavy-duty slewing bearing, the upper and lower rows of balls bear axial force and overturning moment respectively, allowing for simultaneous bearing of large radial loads, axial loads, and overturning moments, significantly improving overall load-bearing capacity. The double-row ball layout also results in minimal radial and axial clearance of the slewing bearing, eliminating wobbling during rotation and improving the positioning stability of the gripper during load tests.

[0053] In Example 6, as a further preferred embodiment of Example 1, the rotary drive mechanism 2 also integrates a rotary self-locking device. This device is a hydraulic lock installed on the rotary control oil circuit of the rotary drive mechanism 2. When the hydraulic motor stops supplying oil, the hydraulic lock cuts off the oil circuit to lock the hydraulic motor output shaft, achieving rotary self-locking. By installing a hydraulic lock on the rotary control oil circuit, when the hydraulic motor stops supplying oil, the hydraulic lock immediately cuts off the oil circuit (both the inlet and outlet oil circuits are closed simultaneously), sealing the hydraulic oil on both sides of the hydraulic motor output shaft within the motor cavity. The incompressibility of the hydraulic oil forms a hydraulic brake, forcibly locking the output shaft. This design effectively prevents unintended rotation under the aforementioned operating conditions, ensuring that the gripper can stably maintain the set angle after stopping rotation.

[0054] Furthermore, in specialized engineering tests such as single pile bearing capacity tests and bridge load tests, the placement of cement counterweights requires strict precision (typically, the deviation between the center of the load and the pile center should not exceed 50mm). If the gripper rotates slightly after stopping, the counterweight will deviate from its intended position during descent, requiring repeated adjustments and severely impacting test efficiency. The rotating self-locking device of this invention, combined with a high-precision slewing bearing, can lock instantly after rotation into position, preventing creep and drift and ensuring the gripper angle remains constant. Operators can precisely lower the counterweight vertically to the target position without needing to readjust the rotation angle during descent, significantly improving the accuracy and efficiency of the loading operation.

[0055] Example 7, as a further preferred embodiment of Example 1, also includes a heavy-duty reinforcement structure. This structure includes reinforcing ribs on the outer or inner side of the gripping arm 32, a slewing bearing reinforcement seat between the rotary drive mechanism 2 and the connecting base 1 or hydraulic gripping mechanism 3, and a load-bearing pad on the force-bearing surface of the gripper assembly 4. The gripping arm 32 is the core load-bearing component that transmits gripping force and bears the weight of the material. When gripping heavy materials, the gripping arm bears significant bending moments and torsional loads, especially in the stress concentration area between the middle of the gripping arm (the hinge point of the hydraulic cylinder piston rod) and the free end (the mounting point of the gripper assembly). By providing reinforcing ribs (usually arranged along the length of the gripping arm, with a thickness of 12mm or more) on the outer or inner side of the gripping arm, the moment of inertia of the gripping arm section is effectively increased, significantly improving its bending stiffness and torsional strength. Furthermore, the hinge points between the clamping arm and the fixed base 31 (at the first pin 35), the hinge points with the hydraulic cylinder piston rod (at the third pin 37), and the mounting position of the gripper assembly are all high stress concentration areas. The reinforcing ribs can disperse the stress in these areas over a wider range, avoiding excessive stress concentration at the weld or abrupt changes in cross-section, thereby effectively preventing weld cracking or base body fracture of the clamping arm under long-term heavy-load fatigue conditions.

[0056] The slewing bearing 22 is a key rotating component connecting the connecting base 1 and the hydraulic clamping mechanism 2. It bears the vertical pressure applied by the excavator boom, the overturning moment generated when gripping materials, and the impact torque during rotation start-up and shutdown. Under heavy-load conditions, the connection points between the slewing bearing and the connecting base and fixed seat 31 are prone to fretting wear or bolt loosening. To address this, a slewing bearing reinforcement seat (usually made of integral cast steel or a welded structure of thick steel plate) is placed between the rotary drive mechanism 2 and the connecting base 1, or between the rotary drive mechanism 2 and the hydraulic clamping mechanism 3. This effectively increases the contact area between the end face of the slewing bearing and the connecting base or fixed seat, reduces the contact surface pressure, and prevents local crushing.

[0057] The gripper assembly 4 is the final load-bearing component that directly contacts the material and bears its weight. When gripping heavy materials (such as cement counterweights and large steel sections), the bottom of the gripper's hook groove and the inner side of the clamping panel bear extremely high contact stress. If this stress were directly borne by a steel plate of ordinary thickness, localized dents, wear, or even breakage would easily occur after long-term use. Therefore, high-strength wear-resistant alloy steel load-bearing pads (HRC≥58) are used for localized reinforcement in the key load-bearing areas at the bottom of the gripper's hook groove and on the inner side of the clamping panel. This significantly increases the thickness of the load-bearing surface, thereby improving its resistance to crushing and preventing permanent dents even under long-term heavy loads.

[0058] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-functional rotary excavator attachment, characterized in that: It includes a connecting base (1), a rotary drive mechanism (2), and a hydraulic clamping mechanism (3). The connecting base (1) is used to form a detachable fixed connection with the front end of the excavator's boom. The rotary drive mechanism (2) is installed below the connecting base (1) and is used to drive the entire hydraulic clamping mechanism (3) to achieve 360-degree stepless continuous rotation in the horizontal plane. The hydraulic clamping mechanism (3) is connected below the rotary drive mechanism (2). The hydraulic clamping mechanism (3) includes a fixed base (31), which is fixedly installed on the rotary output component of the rotary drive mechanism (2). A pair of clamping arms (32) are symmetrically arranged on both sides below the fixed base (31). One end of the clamping arm (32) is hinged to the fixed base (31) through a first pin (35). A hydraulic cylinder mounting base (3) is fixedly welded in the middle of the fixed base (31). 3) A pair of hydraulic cylinders (34) are symmetrically arranged on both sides of the hydraulic cylinder mounting base (33). The hydraulic cylinders (34) are located above the clamping arm (32). The cylinder bodies of the two hydraulic cylinders (34) are respectively hinged to the hydraulic cylinder mounting base (33) through the second pin (36). The piston rods of the two hydraulic cylinders (34) are respectively hinged to the middle of the clamping arm (32) on the corresponding side through the third pin (37). The free end of the clamping arm (32) is equipped with a claw assembly (4).

2. The multi-functional rotary excavator attachment according to claim 1, characterized in that: The gripper assembly (4) includes a clamping panel (41) and a hidden hook (42). The clamping panel (41) is fixedly welded to the free end of the clamping arm (32). The inner side of the clamping panel (41) protrudes from the free end of the clamping arm (32) to form a planar clamping part for clamping the workpiece. The inner sides of the clamping arm (32) and the clamping panel (41) are provided with through mounting slots (43). The inner side and the bottom of the mounting slots (43) are open. The mounting slots (43) are hinged to one end of the hidden hook (42) through the fourth pin (45). The other end of the hidden hook (42) is bent to form a hook-shaped structure. When the hidden hook (42) rotates around the fourth pin (45) to the working state, the hook-shaped structure of the hidden hook (42) extends out of the bottom of the clamping panel (41) and the hook tip faces the inner side of the clamping arm (32).

3. The multi-functional rotary excavator attachment according to claim 2, characterized in that: The concealed hook (42) has a limiting hole in the middle, and the clamping arm (32) has two positioning through holes on its side that extend along the thickness direction of the clamping arm. The two positioning through holes are symmetrically arranged on both sides of the fourth pin (45). The limiting hole and any positioning through hole are engaged by a pin (44). When the concealed hook (42) is in the extreme position of being fully extended or fully retracted, the pin (44) is inserted into the limiting hole and the corresponding positioning through hole to realize the mechanical positioning and locking of the concealed hook (42) in the two working postures.

4. A multi-functional rotary excavator attachment according to claim 2, characterized in that: The inner surface of the hook groove of the concealed hook (42) is provided with anti-slip and wear-resistant teeth.

5. A multi-functional rotary excavator attachment according to claim 2, characterized in that: The concealed hook (42) has a steel adapter slot in its hook groove.

6. A multi-functional rotary excavator attachment according to claim 2, characterized in that: The outer side of the planar clamping part of the clamping panel (41) is provided with a chamfered transition, and a rubber anti-slip pad is fixedly installed on the upper surface of the planar clamping part of the clamping panel (41).

7. A multi-functional rotary excavator attachment according to claim 1, characterized in that: The rotary drive mechanism (2) includes a hydraulic motor and a slewing bearing. The outer ring of the slewing bearing is fixedly connected to the lower end face of the connecting base (1), and the inner ring of the slewing bearing is fixedly connected to the upper end face of the fixed seat (31). The housing of the hydraulic motor is fixedly installed on the connecting base (1) or the outer ring of the slewing bearing. The output shaft of the hydraulic motor is coaxially fixedly mounted with a transmission gear. The transmission gear meshes with the gear ring of the inner ring of the slewing bearing. The hydraulic motor drives the inner ring and the outer ring of the slewing bearing to rotate relative to each other through the transmission gear, thereby driving the hydraulic clamping mechanism (3) to achieve 360-degree continuous rotation in the horizontal plane relative to the connecting base (1).

8. A multi-functional rotary excavator attachment according to claim 7, characterized in that: The slewing bearing is a double-row ball bearing heavy-duty slewing bearing. The outer ring of the slewing bearing is fixedly connected to the connecting base (1) by a high-strength bolt group. The inner ring of the slewing bearing is fixedly connected to the upper end plate of the fixed seat (31) by a high-strength bolt group. The hydraulic motor is a high-torque low-speed hydraulic motor. The housing of the hydraulic motor is installed on the lower surface of the connecting base (1) through a flange.

9. A multi-functional rotary excavator attachment according to claim 1, characterized in that: The rotary drive mechanism (2) also integrates a rotary self-locking device, which is a hydraulic lock installed on the rotary control oil circuit of the rotary drive mechanism (2). When the hydraulic motor stops supplying oil, the hydraulic lock cuts off the oil circuit to lock the output shaft of the hydraulic motor, thereby achieving rotary self-locking.

10. A multi-functional rotary excavator attachment according to claim 1, characterized in that: It also includes a heavy-duty reinforcement structure, which includes a reinforcing rib plate disposed on the outside or inside of the clamping arm (32), a slewing bearing reinforcement seat disposed between the rotary drive mechanism (2) and the connecting base (1) or the hydraulic clamping mechanism (3), and a load-bearing pad disposed on the force-bearing surface of the gripper assembly (4).

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