A trigger-type rapid grasping underactuated finger mechanism

Abstract

The present invention relates to the field of robotics technology, and specifically discloses a trigger-type rapid grasping under-actuated finger mechanism, comprising a carrier, a trigger, a drive rod, a clamping claw assembly and a reset assembly; a clamping area is provided below the carrier, the trigger linkage controls the opening and closing of the locking mechanism, and the drive rod is elastically connected to the carrier through a first elastic body; the base end of the clamping claw assembly is hinged to the drive rod, and is composed of a plurality of hinged knuckles, and a negative angle energy storage state is formed between adjacent knuckles through a second elastic body. When an object triggers the locking mechanism to release the drive rod, the first elastic body drives the clamping claw assembly to swing toward the clamping area, and each knuckle closes step by step according to the contact sequence: the opening angle of the adjacent joints of the blocked knuckle turns from negative to positive, and the second elastic body generates an additional closing force when it crosses the critical point; the unblocked knuckle continues to close under the pulling force of the drive rod. Through the synergistic effect of pure mechanical triggering and elastic body energy storage, millisecond-level response grasping, dynamic superposition of closing force and multi-scenario adaptive clamping effects are achieved.

Description

Technical Field

[0001] The present invention relates to the field of robotics technology, and in particular to a trigger-type rapid-grasping under-actuated finger mechanism. Background Art

[0002] In recent years, underactuated manipulators have garnered widespread attention in the field of industrial gripping due to their simple structure and strong adaptability. Underactuated mechanisms, through the synergy of passive degrees of freedom between joints and elastic elements, can automatically adjust the gripping configuration based on the object's shape, reducing the number of actuating sources and lowering control complexity.

[0003] However, existing underactuated grippers still face the following problems in practical applications: Traditional underactuated grippers often rely on complex drive systems to achieve grasping movements. For example, Chinese patent publication No. CN213439732U proposes an adaptive flexible robotic gripper based on an underactuated mechanism. This gripping mechanism uses a hydraulic push mechanism and force feedback control to achieve adaptive grasping. During the grasping process, sensors detect the contact force in real time and feed it back to the drive device to adjust the gripping posture. This design, which relies on an electronic control system, not only leads to response delays but is also prone to grasping failures due to signal transmission lags in scenarios where objects are moving rapidly. Furthermore, the introduction of a hydraulic drive unit and sensor module significantly increases the structural complexity and manufacturing costs.

[0004] Another type of improvement scheme, such as the master-slave power-driven adaptive under-actuated gripper disclosed in Chinese patent publication number CN210704871U, achieves dual-mode clamping through a master-slave power drive structure. Although its mirror-symmetrical clamping components can switch between parallel clamping and envelope clamping, it relies on the lifting drive component to drive multiple sets of articulated connecting rods to achieve motion transmission, resulting in mechanical structure redundancy and stringent assembly precision requirements. In addition, the linkage transmission limits the independent movement ability of each gripper, making it difficult to adapt to the grasping of asymmetric and special-shaped objects.

[0005] In addition, existing under-actuated mechanisms generally have a contradiction between control accuracy and structural simplification: although adding drive units or sensors can improve grasping stability, it deviates from the original intention of lightweight under-actuated design; and although relying solely on spring energy storage can quickly release driving force, it lacks a trigger mechanism and a step-by-step locking mechanism, resulting in the joints being unable to adaptively lock according to the contact sequence during the grasping process, which can easily lead to problems such as insufficient clamping force or object slippage.

[0006] The above technical defects highlight the imbalance between fast response, simple structure and strong adaptability of the current under-actuated trigger-type rapid grasping under-actuated finger mechanism. There is an urgent need for a solution that does not require a complex electronic control system and can achieve step-by-step closure through pure mechanical triggering to meet the dual needs of instantaneous grasping and stable clamping. Summary of the Invention

[0007] In view of the above-mentioned deficiencies in the prior art, an object of the present invention is to provide a trigger-type quick-grip under-actuated finger mechanism to solve the above-mentioned problems.

[0008] A trigger-type rapid grasping underactuated finger mechanism, comprising:

[0009] a carrier having a gripping area provided below the carrier;

[0010] a trigger, provided on the carrier and corresponding to the clamping area;

[0011] The driving rod is elastically connected to the carrier through the first elastic body, and its initial position is fixed by the locking mechanism, and the trigger is linked to control the opening and closing of the locking mechanism;

[0012] At least two clamping jaw assemblies are arranged around the center of the clamping area and the base ends are hinged to the driving rod. The clamping jaw assembly includes a plurality of finger joints hinged in sequence. Adjacent finger joints are connected by a second elastic body and form an energy storage state with a negative opening angle. When an object triggers the trigger, the locking mechanism releases the driving rod, and the first elastic body drives the clamping jaw assembly to swing toward the clamping area. Each finger joint is triggered to close step by step according to the order of contact with the object, that is, when any finger joint is blocked from contacting the object, the opening angle between it and the adjacent finger joint changes from negative to positive, and the second elastic body generates additional closing force when it crosses the critical point. The unblocked finger joints continue to rotate around the hinge axis of the driving rod under the pulling force of the driving rod, thereby realizing adaptive closure of the remaining finger joints.

[0013] The reset assembly is used to drive the driving rod to return to its initial position after the grasping action is completed and to be re-fixed and locked by the locking mechanism, and to drive each of the clamping jaw assemblies and their knuckles to reset to the initial open state.

[0014] Specifically, the trigger includes a push switch that can be triggered by an object, and a push rod linked to the push switch, and the push rod is mechanically linked to the locking mechanism.

[0015] Specifically, the locking mechanism includes two hanging rods hinged at the top to the carrier, an elastic reset part connecting the two hanging rods, and a wedge-shaped inclined surface formed between the two hanging rods; when the push rod is pushed in, the two hanging rods are separated by the wedge-shaped inclined surface to release the driving rod.

[0016] Specifically, a rotation limiting structure is provided between two adjacent finger joints to limit the maximum negative angle of the two.

[0017] Specifically, the rotation limiting structure includes a limiting blocking surface provided on the finger joint and a limiting boss provided on the adjacent finger joint. When the finger joint rotates to the maximum negative angle, the limiting blocking surface abuts against the limiting boss.

[0018] Specifically, the maximum negative angle is -5°.

[0019] Specifically, the first elastic body and the second elastic body are both tension springs.

[0020] Specifically, the clamping jaw assembly further includes a connecting rod assembly, which includes a first connecting rod and a second connecting rod respectively hinged to two adjacent finger joints, and the first connecting rod and the second connecting rod are hinged to each other.

[0021] Specifically, the connecting rod assembly further includes a third connecting rod, one end of the third connecting rod is hinged to the driving rod, and the other end of the third connecting rod is hinged to the adjacent first connecting rod.

[0022] Specifically, the reset component includes:

[0023] a motor fixed to the carrier;

[0024] A reel mounted on the motor output shaft; and

[0025] a draw rope wound around the reel;

[0026] wherein the distal end of the pull cord is connected to the end of the knuckle farthest from the trigger;

[0027] The motor drives the reel to rotate and reel in the rope, pulling the various fingers of the clamping jaw assembly to expand outward synchronously until all the clamping jaw assemblies are reset to the initial open state.

[0028] Beneficial effects of the present invention:

[0029] 1. The trigger-type rapid grasping under-actuated finger mechanism of this application releases the lock and releases the elastic potential energy through purely mechanical linkage, eliminating the signal transmission and drive adjustment steps of the traditional electronic control system. The grasping action is completed at the moment of triggering, making it suitable for high-speed production line scenarios.

[0030] 2. Each knuckle locks or releases autonomously based on the order of contact, and dynamic superposition of closing force is achieved through the switching of the critical points of the second elastic body. This ensures flexible gripping of lightly touched objects while providing progressively stronger gripping force for heavy objects.

[0031] 3. A single drive rod synchronously controls multiple gripper assemblies, allowing for adaptability to objects of varying shapes by adjusting the symmetrical or staggered layout of the grippers. The number of joints can be expanded without adding additional drive elements.

[0032] 4. Each gripper assembly operates independently. Even if the object is asymmetrical or offset, it can still achieve stable grasping through partial knuckle closure, avoiding the overall loss of control caused by single-point failure of traditional linkage mechanisms. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A three-dimensional diagram of the trigger-type rapid grasping under-actuated finger mechanism of the present application;

[0034] Figure 2 A cross-sectional view of the trigger-type quick-grasp under-actuated finger mechanism of the present application;

[0035] Figure 3 A stereoscopic diagram of the trigger-type rapid grasping under-actuated finger mechanism of the present application applied to scene a;

[0036] Figure 4 for Figure 3 Enlarged view of part A;

[0037] Figure 5 This is a front view of the trigger-type rapid grasping under-actuated finger mechanism of the present application applied to scene a, where the dotted line portion in the figure refers to the object being gripped;

[0038] Figure 6 This is a front view of the trigger-type rapid grasping under-actuated finger mechanism of this application applied to scene b, where the dotted line portion indicates the object being gripped;

[0039] Figure 7 This is the main view of the trigger-type rapid grasping under-actuated finger mechanism of this application applied to scene c, and the dotted part in the figure refers to the clamped object.

[0040] The figures are marked as: carrier 10, clamping area 11, trigger 20, drive rod 30, first elastic body 40, second elastic body 41, locking mechanism 50, clamping claw assembly 60, finger heel 61, middle finger joint 62, fingertip 63, press switch 21, push rod 22, hanging rod 51, wedge-shaped inclined plane 52, rotation limiting structure 70, limiting blocking surface 71, limiting boss 72, connecting rod assembly 80, first connecting rod 81, second connecting rod 82, third connecting rod 83, reset assembly 90, motor 91, reel 92, pull rope 93, guide inclined plane 53. DETAILED DESCRIPTION

[0041] The present invention provides a trigger-type rapid-grip underactuated finger mechanism. To make the objectives, technical solutions, and effects of the present invention more clear and explicit, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention.

[0042] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0043] Please refer to Figures 1 to 7 , a trigger-type rapid grasping under-actuated finger mechanism of this embodiment includes:

[0044] The carrier 10 has a clamping area 11 provided below it;

[0045] A trigger 20 is provided on the carrier 10 and corresponds to the clamping area 11;

[0046] The driving rod 30 is elastically connected to the carrier 10 through the first elastic body 40. The initial position is fixed by the locking mechanism 50. The trigger 20 controls the opening and closing of the locking mechanism 50.

[0047] At least two clamping jaw assemblies 60 are arranged around the center of the clamping area 11 and the base ends are hinged to the driving rod 30. Each clamping jaw assembly 60 includes a finger heel 61, a middle finger joint 62, and a fingertip 63 that are hinged in sequence. In the initial state, the finger heel 61 and the middle finger joint 62 are connected by the second elastic body 41 and form an energy storage state with a negative opening angle. The middle finger joint 62 and the fingertip 63 are also connected by the second elastic body 41 and form an energy storage state with a negative opening angle. When the object triggers the trigger 20, the locking mechanism The mechanism 50 releases the drive rod 30, and the first elastic body 40 drives the clamping jaw assembly 60 to swing toward the gripping area 11. Each knuckle (heel 61, middle knuckle 62, and fingertip 63) triggers a step-by-step closing according to the order in which they contact the object: when any knuckle is blocked from contacting the object, the angle between it and the adjacent knuckle turns from negative to positive, and the second elastic body 41 generates additional closing force when it crosses the critical point. The unblocked knuckles continue to rotate around the hinge axis of the drive rod 30 under the pulling force of the drive rod 30, achieving adaptive closure of the remaining knuckles.

[0048] The reset assembly 90 is used to drive the driving rod 30 to return to its initial position after the grasping action is completed and to be re-fixed and locked by the locking mechanism 50, and to drive each clamping jaw assembly 60 and its knuckles to return to the initial open state.

[0049] It should be noted that in this embodiment, two gripper assemblies 60 are used, and they are arranged in a bilaterally symmetrical layout. Each gripper assembly 60 has three finger joints (the heel 61, the middle finger joint 62, and the fingertip 63). In other embodiments, the number of gripper assemblies 60 is not limited to two, and can be three or four, etc. The layout of the gripper assemblies 60 can be staggered, spatially symmetrical, etc., and the number of finger joints can be more than three.

[0050] The gripping process of the device is achieved by the synergistic effect of mechanical triggering and underactuation: when the object enters the gripping area 11 and presses the push switch 21 of the trigger 20, the push rod 22 is driven by the linkage to push laterally into the wedge-shaped inclined surface 52 of the locking mechanism 50, forcing the two hanging rods 51 to separate (such as Figure 3 and Figure 4 ), release the horizontal lock of the driving rod 30. At this time, the pre-stored elastic potential energy of the first elastic body 40 is released, and the driving rod 30 quickly swings downward around its hinge axis, driving each clamping jaw assembly 60 to retract toward the center of the clamping area 11 (as shown in FIG. Figure 5 ).

[0051] In the initial state, the heel 61, middle knuckle 62 and fingertip 63 of the clamping jaw assembly 60 are maintained in an open posture with a negative angle of -5° by the second elastic body 41, forming an energy storage state.

[0052] When the driving rod 30 swings, each clamping jaw assembly 60 rotates inward synchronously under the drive of the driving rod 30, and each finger joint triggers the step-by-step closing mechanism according to the order of contact with the object. The specific scenario is as follows:

[0053] Scenario a (fingertip 63 first contact): Figure 5 As shown, when the object is small or located in the lower center of the clamping area 11, the fingertip 63 of the clamping jaw assembly 60 first contacts the surface of the object. At this time, the fingertip 63 is blocked by the reaction force of the object, and the hinge axis between the middle finger joint 62 and the fingertip 63 stops rotating due to the obstruction. The second elastic body 41 between the two is still in a negative angle state and has not crossed the critical point to release the stored energy. At the same time, the continuous downward pull of the driving rod 30 locks the hinge axis between the finger heel 61 and the middle finger joint 62, causing the finger heel 61 to be unable to continue to rotate. Finally, only the fingertip 63 is tightly attached to the object under the tension of the tension spring of the driving rod 30 to complete the grip. The gripping force is completely provided by the first elastic body 40, forming a stable single-point clamping.

[0054] Scenario b (the heel 61 and the middle knuckle 62 are closed, and the fingertip 63 is suspended): Figure 6As shown, when there is a local depression on the surface of an object or the gripping position is close to the base of the gripper, the heel 61 and middle phalanx 62 may first contact the object. For example, when gripping a workpiece with a stepped structure, the heel 61 is blocked and stops rotating after contacting the upper side of the workpiece. The continued pulling force of the drive rod 30 forces the middle phalanx 62 to continue rotating about the hinge axis of the heel 61. When the opening angle between the middle phalanx 62 and the heel 61 changes from -5° to a positive angle, the second elastic body 41 between them crosses the critical point, releasing stored energy and generating additional closing force, causing the middle phalanx 62 to quickly press against the object surface. At the same time, the hinge axis between the middle phalanx 62 and the fingertip 63 is blocked by the object's contour or insufficient gripping depth (e.g., a low workpiece height), preventing the fingertip 63 from further inward rotation. Its opening angle remains negative, and the second elastic body 41 does not trigger the critical point transition, leaving the fingertip 63 in a suspended, unclosed position. In this scenario, the grasping action is completed by the heel 61 and the middle knuckle 62 in coordination, forming a two-point support grasping. The grasping force is jointly provided by the first elastic body 40 of the driving rod 30 and the second elastic body 41 between the heel 61 and the middle knuckle 62. It is suitable for flat or stepped objects that have low grasping accuracy requirements but need to be quickly fixed.

[0055] Scenario c (middle finger joint 62 first contact): Figure 7 As shown, if the object is of moderate height and the gripping position is slightly upward, the middle phalanx 62 will preferentially contact the object. At this point, the hinge axis between the heel 61 and the middle phalanx 62 is blocked, and the heel 61 stops rotating. However, the pulling force of the drive rod 30 continues to act on the middle phalanx 62 and the fingertip 63. When the middle phalanx 62 and the fingertip 63 continue to rotate inward about their hinge axis until the opening angle changes from -5° to a positive angle, the second elastic body 41 between them passes the critical point, and the elastic potential energy is instantly released and converted into additional closing force, pushing the fingertip 63 to accelerate and clamp the object. During this process, the heel 61 remains stationary, while the middle phalanx 62 and the fingertip 63 cooperate to form a two-point enveloping grip, with the gripping force provided by both the first elastic body 40 and the second elastic body 41.

[0056] Scenario d (heel 61 contacts first): When grasping a large or high object, heel 61 contacts the object first. Due to the continued downward pull of the drive rod 30, the middle knuckle 62 continues to rotate around its hinge axis with the heel 61 until the opening angle between the middle knuckle 62 and the heel 61 changes from -5° to a positive angle. The second elastic member 41 between them crosses the critical point, releasing stored energy and generating additional closing force, causing the middle knuckle 62 to rapidly press against the object. Then, due to frictional contact with the object, the middle knuckle 62 is fixed. Under the continued downward pull of the drive rod 30, the fingertip 63 continues to rotate around its hinge axis with the middle knuckle 62 until the opening angle between the middle knuckle 62 and the fingertip 63 changes from -5° to a positive angle. At this point, the second elastic member 41 between them crosses the critical point, instantly releasing the elastic potential energy and converting it into additional closing force, pushing the fingertip 63 to accelerate the compression of the object, forming an enveloping grasping structure. Finally, the heel 61, the middle finger joint 62, and the fingertip 63 are closed in sequence to form a three-point adaptive envelope grasping, and the grasping force is maximized by the coordinated action of the three groups of elastic bodies.

[0057] It should be added that Figures 5 to 7 When the clamping jaw assembly 60 is triggered to clamp, in order to prevent the second elastic body 41 from contacting the clamped object, the thickness of the finger joints can be increased to avoid interference.

[0058] This device significantly improves the grasping efficiency and adaptability through the mechanical triggering and the step-by-step closing mechanism of the under-actuated mechanism. Its core advantages are:

[0059] The system releases the lock and releases the elastic potential energy through pure mechanical linkage, eliminating the signal transmission and drive adjustment steps of the traditional electronic control system. The grasping action is completed at the triggering moment, which is suitable for high-speed production line scenarios.

[0060] Each knuckle locks or releases autonomously according to the contact sequence, and the closing force is dynamically superimposed by switching the critical points of the second elastic body 41, which not only ensures the flexible grasping of lightly touched objects, but also provides a gradually enhanced gripping force for heavy objects;

[0061] A single drive rod 30 is used to synchronously control multiple sets of gripper assemblies 60. The symmetrical or staggered layout of the grippers can be adjusted to accommodate objects of different shapes, and the number of joints can be expanded without adding additional drive elements.

[0062] Each gripper assembly 60 operates independently, and even if the object is asymmetrical in shape or offset in placement, it can still achieve stable grip through partial knuckle closure, avoiding the overall loss of control problem caused by single-point failure of traditional linkage mechanisms.

[0063] In general, this solution uses a purely mechanical structure to achieve fast triggering and adaptive grasping, simplifying the mechanism while taking into account grasping accuracy and reliability. It is especially suitable for precision grasping scenarios such as electronic components and special-shaped workpieces.

[0064] As a preferred embodiment, the first elastomer 40 and the second elastomer 41 of this embodiment both adopt tension springs. The tension springs have the characteristics of compact structure, easy installation, and obvious linear elastic characteristics. They can accurately control the critical points of energy storage and release, ensuring the rapid swing of the drive rod 30 and the instantaneous angle conversion between the knuckles; at the same time, the pre-tension of the tension spring is flexibly adjusted, and different gripping force requirements can be matched by adjusting the installation position or the diameter of the spring wire. It is low-cost and highly reliable, and is suitable for batch applications in industrial scenarios.

[0065] It should be noted that the tension spring is only one preferred embodiment of an elastic element. In other embodiments, those skilled in the art may select a functionally equivalent elastic element as a substitute based on actual needs. For example, elastic cords, silicone elastomers, and other materials may also be used to achieve nonlinear elastic properties. Simple variations or combinations of the aforementioned elastic elements, as long as they can achieve the technical effects of energy storage triggering, critical point locking, and adaptive gripping, fall within the scope of protection of the present claims.

[0066] For further information, please refer to Figures 1 to 4 The trigger 20 includes a push switch 21 that can be triggered by an object, a push rod 22 that is linked to the push switch 21, and a locking mechanism 50 that includes two hanging rods 51 hinged at their tops to the carrier 10, and an elastic reset member connecting the two hanging rods 51. A wedge-shaped inclined surface 52 is formed between the two hanging rods 51. When the push rod 22 is pushed in, the two hanging rods 51 are separated by the wedge-shaped inclined surface 52 to release the driving rod 30. The push switch 21 adopts a mechanical contact trigger design. When an object enters the clamping area 11 and touches the push switch 21, the vertical pressure exerted by the object forces the push switch 21 to move upward. Under the action of the connecting rod, the push rod 22 is driven to insert laterally into the wedge-shaped inclined surface 52 between the two hanging rods 51 of the locking mechanism 50. The inclined surface slides and squeezes the two hanging rods 51, forcing them to separate outward, overcoming the pulling force of the elastic reset member, thereby releasing the locking constraint on the driving rod 30. This purely mechanical linkage trigger mechanism requires no external energy or electrical control signals, completing the locking and releasing action the instant the object makes contact, achieving millisecond-level response. This completely eliminates the risk of grasping failure caused by signal transmission and processing delays in traditional electronically controlled sensing systems. Furthermore, the modular design of the push switch 21 and push rod 22 ensures high robustness, enabling stable operation in harsh industrial environments such as dust and oil, while maintaining significantly lower maintenance costs than hydraulic or pneumatic triggering devices.

[0067] like Figure 2As shown, a rotational stop structure 70 is provided between two adjacent knuckles to limit their maximum negative angle. The rotational stop structure 70 comprises a stop surface 71 on the knuckle and a stop boss 72 on the adjacent knuckle. When the knuckle rotates to its maximum negative angle, the stop surface 71 abuts the stop boss 72. The maximum negative angle is R, where R = -5°. Specifically, when the knuckles (e.g., the middle knuckle 62 and the fingertip 63) are in their initial open position, the stop surface 71 at the end of the fingertip 63 abuts the stop boss 72 at the base of the middle knuckle 62, forming a rigid barrier that prevents further reverse opening of the fingertip 63. This design precisely controls the negative angle range, ensuring that the preload force of the second elastic body 41 is within the optimal energy storage range. This prevents excessive spring stretching and elastic failure, while also providing sufficient potential energy reserve for the angle to transition from negative to positive when the closure is triggered.

[0068] Please refer to Figure 3 The clamping jaw assembly 60 also includes a connecting rod assembly 80, which includes a first connecting rod 81 hinged to the middle finger joint 62 and a second connecting rod 82 hinged to the fingertip 63, and the first connecting rod 81 and the second connecting rod 82 are hinged to each other; the connecting rod assembly 80 also includes a third connecting rod 83, one end of the third connecting rod 83 is hinged to the driving rod 30, and the other end is hinged to the adjacent first connecting rod 81.

[0069] The connecting rod assembly 80 achieves motion coupling between the drive rod 30 and each finger joint through a multi-stage hinge structure: when the drive rod 30 is driven downward by the first elastic body 40, the third connecting rod 83 pulls the first connecting rod 81 to rotate around the middle finger joint 62, forcing the middle finger joint 62 to deflect inward. At the same time, the hinge point between the first connecting rod 81 and the second connecting rod 82 transmits torque to the fingertip 63, driving it to close synchronously. If a finger joint is blocked from contact with an object, the pulling force of the drive rod 30 is forcibly distributed to the unblocked finger joint through the third connecting rod 83 and the first connecting rod 81, ensuring that the closing action is completed according to the preset trajectory. This design of coordinated rigid connecting rods and elastic bodies precisely defines the swing angle of the finger joints through a four-bar mechanism. Not only does it achieve synchronous drive of multiple joints with fewer parts, avoiding the motion disorder problem of a purely elastic system, but it also allows the number of finger joints to be expanded by adding connecting rod modules. Compared with traditional multi-stage transmission structures, this can reduce the number of parts, significantly improving grasping stability and assembly efficiency while maintaining under-actuated adaptive characteristics.

[0070] As a preferred embodiment, Figure 1As shown, the reset assembly 90 includes a motor 91 fixed to the carrier 10, a reel 92 mounted on the output shaft of the motor 91, and a pull rope 93 wound around the reel 92; wherein the distal end of the pull rope 93 is connected to the end of the finger joint farthest from the trigger 20 (i.e., the fingertip 63 in this embodiment); the motor 91 drives the reel 92 to rotate and reel in the rope, pulling the various finger joints of the clamping jaw assembly 60 to expand outward synchronously until all the clamping jaw assemblies 60 are reset to the initial open state. When it is necessary to put down an item, the motor 91 drives the reel 92 to rotate and reel in the rope, and the pull rope 93 is used to pull the clamping jaw assembly 60 to fully expand and restore it to the initial pre-tightened energy storage state. At this time, the item is no longer clamped and falls, and at the same time, the drive rod 30 is driven to return and is fixed by the locking mechanism 50, ensuring that the entire mechanism automatically and completely resets to the ready-to-trigger state without the need for manual reset.

[0071] In addition, in order to make it easier to reset the driving rod 30 and ensure that it is reliably locked by the locking mechanism 50 after being reset, as shown in FIG. Figure 4 As shown, this embodiment adds two guiding slopes 53 at the bottom of the two hanging rods 51 to form an eight-shaped guide structure. When the motor 91 drives the winding reel 92 to reel in the rope and pulls the clamping jaw assembly 60, the clamping jaw assembly 60 drives the drive rod 30 to slide upward along the eight-shaped guide structure, gradually spreading the two hanging rods 51 apart, ultimately allowing the drive rod 30 to smoothly engage the locking groove between the two hanging rods 51. Subsequently, under the pulling force of the elastic return member, the two hanging rods 51 return to their original position and close, locking the drive rod 30.

[0072] The above specifically describes the preferred embodiments of the present invention, but the present invention is not limited to the embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of the present invention.

Claims

1. A trigger-type rapid grasping underactuated finger mechanism, characterized in that: include: A carrier (10) having a clamping area (11) provided below the carrier; A trigger (20) is provided on the carrier (10) and corresponds to the clamping area (11); The driving rod (30) is elastically connected to the carrier (10) via a first elastic body (40), and its initial position is fixed by a locking mechanism (50); the trigger (20) controls the opening and closing of the locking mechanism (50) in a linked manner; At least two clamping jaw assemblies (60) are arranged around the center of the clamping area (11) and the base ends are hinged to the driving rod (30), the clamping jaw assembly (60) includes a plurality of finger joints hinged in sequence, and the adjacent finger joints are connected by a second elastic body (41) and form an energy storage state with a negative opening angle; when the object triggers the trigger (20), the locking mechanism (50) releases the driving rod (30), and the first elastic body (40) drives the clamping jaw assembly (60) to swing toward the clamping area (11), and each finger joint is triggered to close step by step according to the order of contacting the object, that is: when any finger joint is blocked from contacting the object, the opening angle between it and the adjacent finger joint changes from negative to positive, and the second elastic body (41) crosses the critical point to generate additional closing force; the unblocked finger joints continue to rotate around the hinge axis of the driving rod (30) under the pulling force of the driving rod (30), so as to realize the adaptive closing of the remaining finger joints; A reset assembly (90) is used to drive the driving rod (30) back to its initial position after the grasping action is completed and to be re-fixed and locked by the locking mechanism (50), and to drive each of the clamping jaw assemblies (60) and their knuckles to reset to the initial open state; The trigger (20) includes a push switch (21) that can be triggered by an object, and a push rod (22) that is linked to the push switch (21), and the push rod (22) is mechanically linked to the locking mechanism (50); The locking mechanism (50) comprises two hanging rods (51) whose tops are hinged to the carrier (10), and an elastic reset member connecting the two hanging rods (51), wherein a wedge-shaped inclined surface (52) is formed between the two hanging rods (51); when the push rod (22) is pushed in, the two hanging rods (51) are separated by the wedge-shaped inclined surface (52) to release the driving rod (30).

2. The trigger-type rapid grasping underactuated finger mechanism according to claim 1, characterized in that: A rotation limiting structure (70) is provided between two adjacent finger joints to limit the maximum negative angle of the two.

3. The trigger-type rapid grasping underactuated finger mechanism according to claim 2, characterized in that: The rotation limiting structure (70) comprises a limiting blocking surface (71) provided on the finger joint and a limiting boss (72) provided on an adjacent finger joint. When the finger joint rotates to a maximum negative angle, the limiting blocking surface (71) abuts against the limiting boss (72).

4. The trigger-type rapid grasping underactuated finger mechanism according to claim 2, characterized in that: The maximum negative angle is -5°.

5. The trigger-type rapid grasping underactuated finger mechanism according to claim 1, characterized in that: The first elastic body (40) and the second elastic body (41) are both tension springs.

6. The trigger-type rapid grasping underactuated finger mechanism according to claim 1, characterized in that: The clamping jaw assembly (60) further comprises a connecting rod assembly (80), wherein the connecting rod assembly (80) comprises a first connecting rod (81) and a second connecting rod (82) respectively hinged to two adjacent finger joints, and the first connecting rod (81) and the second connecting rod (82) are hinged to each other.

7. The trigger-type rapid grasping underactuated finger mechanism according to claim 6, characterized in that: The connecting rod assembly (80) further includes a third connecting rod (83), one end of the third connecting rod (83) being hinged to the driving rod (30), and the other end of the third connecting rod (83) being hinged to the adjacent first connecting rod (81).

8. The trigger-type rapid grasping underactuated finger mechanism according to claim 1, characterized in that: The reset component (90) comprises: a motor (91) fixed to the carrier (10); A winding drum (92) mounted on the output shaft of the motor (91); and a drawstring (93) wound around the reel (92); wherein the distal end of the pull rope (93) is connected to the end of the finger joint farthest from the trigger (20); The motor (91) drives the reel (92) to rotate and reel in the rope, pulling the various fingers of the clamping jaw assembly (60) to expand outward synchronously until all the clamping jaw assemblies (60) are reset to the initial open state.

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