Triggering type quick grasping under-actuated finger mechanism

Abstract

The invention relates to the technical field of robots, and particularly discloses a trigger type quick grabbing under-actuated finger mechanism which comprises a carrier, a trigger, a driving rod, a clamping jaw assembly and a reset assembly. A clamping area is arranged below the carrier, the trigger controls the locking mechanism to be opened and closed in a linkage mode, and the driving rod is elastically connected with the carrier through the first elastic body. The base end of the clamping jaw assembly is hinged to the driving rod, the clamping jaw assembly is composed of a plurality of hinged knuckles, and the adjacent knuckles form a negative-angle energy storage state through second elastic bodies. When an object triggers the locking mechanism to release the driving rod, the first elastic body drives the clamping jaw assembly to swing towards a clamping area, and the knuckles are closed step by step according to the contact sequence: the opening angle of the adjacent joints of the blocked knuckles is changed from negative to positive, and the second elastic body crosses a critical point to generate additional closing force; and the unblocked knuckles are continuously closed under the tension of the driving rod. Through the synergistic effect of pure mechanical triggering and elastomer energy storage, the effects of millisecond-level response grabbing, closing force dynamic superposition and multi-scene self-adaptive clamping are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of robots, and particularly to a trigger-type fast-gripping underactuated finger mechanism. Background Art

[0002] In recent years, underactuated manipulators have received extensive attention in the field of industrial grasping due to their simple structure and strong adaptability. The underactuated mechanism, through the passive degrees of freedom between joints and the cooperation of elastic elements, can automatically adjust the clamping configuration according to the shape of the object, reducing the number of drive sources and the control complexity.

[0003] However, the existing underactuated grippers still have the following problems in practical applications: Traditional underactuated grippers often rely on complex drive systems to achieve grasping actions. For example, an adaptive flexible robotic gripper based on an underactuated mechanism proposed in Chinese Patent Publication No. CN213439732U uses a hydraulic push mechanism and force feedback control to achieve adaptive grasping. During the grasping process, it is necessary to detect the contact force in real time through sensors and feedback it to the drive device to adjust the clamping posture. This design relying on the electronic control system not only causes response delay, but also is prone to grasping failure due to signal transmission lag in scenarios where the object moves rapidly. At the same time, the introduction of the hydraulic drive unit and the sensing module significantly increases the structural complexity and manufacturing cost.

[0004] Another type of improved solution, such as an adaptive underactuated gripper with master-slave power drive disclosed in Chinese Patent Publication No. CN210704871U, realizes 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 a lifting drive component to drive multiple groups of articulated linkages to achieve motion transmission, resulting in redundant mechanical structures, demanding assembly accuracy requirements, and the linkage transmission restricting the independent movement ability of each gripper jaw, making it difficult to adapt to the grasping of asymmetric and irregularly shaped objects.

[0005] In addition, there is generally a contradiction between control accuracy and structural simplification in existing underactuated mechanisms: Increasing the number of drive units or sensors can improve grasping stability, but it deviates from the lightweight original intention of underactuated design; while simply relying on spring energy storage can quickly release the driving force, it lacks a trigger mechanism and a step-by-step locking mechanism, resulting in the inability of the joints to adaptively lock according to the contact sequence during the grasping process, and it is easy to have problems such as insufficient clamping force or object slipping.

[0006] The above technical defects highlight the imbalance of the current underactuated mechanism between fast response, structural simplicity, and strong adaptability. There is an urgent need for a solution that does not require a complex electronic control system and achieves step-by-step closing through pure mechanical triggering to balance the dual requirements 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 quick-grasping underactuated finger mechanism, comprising: a carrier having a gripping area disposed below the carrier; a trigger, disposed on the carrier and corresponding to the clamping area; The driving rod is elastically connected to the carrier through the first elastic body, and the initial position is fixed by the locking mechanism, and the trigger is linked to control the opening and closing of the locking mechanism; 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 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 generates additional closing force when it passes 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 to achieve adaptive closure of the remaining finger joints. 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.

[0009] 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.

[0010] Specifically, the locking mechanism includes two hanging rods hinged at the top to the carrier, and an elastic reset member connecting the two hanging rods, and a wedge-shaped inclined surface is 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.

[0011] Specifically, a rotation limiting structure is provided between two adjacent finger joints to limit the maximum negative angle of the two.

[0012] Specifically, the rotation limiting structure includes a limiting blocking surface provided on the finger joint and a limiting boss provided on an adjacent finger joint. When the finger joint rotates to a maximum negative angle, the limiting blocking surface abuts against the limiting boss.

[0013] Specifically, the maximum negative angle is -5°.

[0014] Specifically, the first elastic body and the second elastic body are both tension springs.

[0015] Specifically, the jaw assembly further includes a linkage assembly. The linkage assembly includes a first link and a second link respectively hinged to adjacent two phalanges, and the first link and the second link are hinged to each other.

[0016] Specifically, the linkage assembly further includes a third link. One end of the third link is hinged to the drive rod, and the other end is hinged to the adjacent first link.

[0017] Specifically, the reset assembly includes: A motor fixed to the carrier; A winding disc mounted on the output shaft of the motor; and A pulling rope wound around the winding disc; Wherein, the distal end of the pulling rope is connected to the end of the phalanx farthest from the trigger; By driving the winding disc to rotate and wind the rope by the motor, each phalanx of the jaw assembly is pulled to expand outward synchronously until all the jaw assemblies are reset to the initial open state.

[0018] Advantages of the present invention: 1. The trigger-type quick-grip underactuated finger mechanism of the present application releases the locking and elastic potential energy through pure mechanical linkage, eliminating the signal transmission and drive adjustment links of the traditional electric control system. The grasping action is completed instantly at the moment of triggering, which is suitable for high-speed production line scenarios; 2. Each phalanx locks or releases independently according to the contact sequence, and the closing force is dynamically superimposed through the critical point switching of the second elastic body, which not only ensures the flexible grasping of light-touch objects, but also can provide gradually enhanced clamping force for heavy objects; 3. A single drive rod synchronously controls multiple groups of jaw assemblies, and different-shaped objects can be adapted by adjusting the symmetrical or staggered layout of the jaws, and the number of joints can be expanded without adding drive elements; 4. Each jaw assembly operates independently. Even if the object shape is asymmetrical or the placement is offset, stable grasping can still be achieved through the closing of local phalanges, avoiding the overall out-of-control problem caused by single-point failure of the traditional linkage mechanism. Description of the Drawings

[0019] Figure 1 Is a perspective view of the trigger-type quick-grip underactuated finger mechanism of the present application; Figure 2 Is a cross-sectional view of the trigger-type quick-grip underactuated finger mechanism of the present application; Figure 3 Is a perspective view of the trigger-type quick-grip underactuated finger mechanism of the present application applied to scenario a; Figure 4 Is Figure 3Enlarged view of part A; Figure 5 This is the front view of the trigger - type quick - grasping under - actuated finger mechanism of this application applied to scenario a. The dotted part in the figure refers to the object to be clamped; Figure 6 This is the front view of the trigger - type quick - grasping under - actuated finger mechanism of this application applied to scenario b. The dotted part in the figure refers to the object to be clamped; Figure 7 This is the front view of the trigger - type quick - grasping under - actuated finger mechanism of this application applied to scenario c. The dotted part in the figure refers to the object to be clamped.

[0020] Reference numerals are: vehicle 10, clamping area 11, trigger 20, drive rod 30, first elastic body 40, second elastic body 41, locking mechanism 50, jaw assembly 60, finger root 61, middle phalanx 62, fingertip 63, push - button switch 21, push rod 22, hanging rod 51, wedge - shaped inclined plane 52, rotation limiting structure 70, limiting blocking surface 71, limiting boss 72, link assembly 80, first link 81, second link 82, third link 83, reset assembly 90, motor 91, winding disc 92, pulling rope 93, guiding inclined plane 53. Detailed implementation manners

[0021] The present invention provides a trigger - type quick - grasping under - actuated finger mechanism. To make the objectives, technical solutions and effects of the present invention clearer and more definite, the following examples are given with reference to the attached drawings for further detailed description of the present invention. It should be understood that the specific examples described herein are only used to explain the present invention and are not used to limit the present invention.

[0022] In the description of the present invention, it should be understood that for the orientation description, such as the upper, lower, front, rear, left, right, etc., the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present invention.

[0023] Please refer to Figures 1 to 7 , a trigger - type quick - grasping under - actuated finger mechanism of this embodiment includes: A vehicle 10, with a clamping area 11 provided below it; A trigger 20, provided on the vehicle 10 and corresponding to the clamping area 11; A drive rod 30, elastically connected to the vehicle 10 through a first elastic body 40, and fixed at the initial position 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 jaw assemblies 60 are arranged around the center of the gripping area 11 and their proximal ends are hinged to the drive rod 30. Each jaw assembly 60 includes a finger base 61, a middle phalanx 62, and a fingertip 63 that are sequentially hinged. In the initial state, the finger base 61 and the middle phalanx 62 are connected by a second elastic body 41 and form an energy storage state with a negative opening angle, and the middle phalanx 62 and the fingertip 63 are also connected by a second elastic body 41 and form an energy storage state with a negative opening angle. When an object triggers the trigger 20, the locking mechanism 50 releases the drive rod 30, and the first elastic body 40 drives the jaw assembly 60 to swing towards the gripping area 11, and each phalanx (finger base 61, middle phalanx 62, fingertip 63) triggers a sequential closing according to the order of contacting the object: when any phalanx contacts the object and is blocked, the opening angle between it and the adjacent phalanx changes from negative to positive, and the second elastic body 41 crosses the critical point to generate an additional closing force; the unblocked phalanx continues to rotate around the hinge axis of the drive rod 30 under the pulling force of the drive rod 30 to achieve the adaptive closing of the remaining phalanx. A reset assembly 90 is used to drive the drive rod 30 to return to its initial position and be re-fixed and locked by the locking mechanism 50 after the grasping action is completed, and drive each jaw assembly 60 and its phalanges to reset to the initial open state.

[0024] It should be noted that two jaw assemblies 60 are used in this embodiment, and they are arranged symmetrically left and right. Each jaw assembly 60 has three phalanges (finger base 61, middle phalanx 62, fingertip 63). In other embodiments, the number of jaw assemblies 60 is not limited to two, and there can be three, four, etc. The layout of the jaw assemblies 60 can be staggered, symmetric in space, etc. In addition, the number of phalanges is not limited to three.

[0025] The grasping process of this device is realized by the synergistic action of mechanical triggering and underactuation: when an object enters the gripping area 11 and presses the push switch 21 of the trigger 20, the push rod 22 is pushed laterally into the wedge-shaped inclined surface 52 of the locking mechanism 50 under the linkage action, forcing the two hanging rods 51 to separate (as Figure 3 and Figure 4 ), and the horizontal locking of the drive rod 30 is released. At this time, the pre-stored elastic potential energy of the first elastic body 40 is released, and the drive rod 30 quickly swings downward around its hinge axis, driving each jaw assembly 60 to converge towards the center of the gripping area 11 (as Figure 5 ).

[0026] The finger base 61, middle phalanx 62, and fingertip 63 of the jaw assembly 60 maintain a negative angle opening posture of -5° through the second elastic body 41 in the initial state to form an energy storage state.

[0027] When the drive rod 30 swings, each jaw assembly 60 synchronously rotates inward under the drive of the drive rod 30, and each phalanx triggers a sequential closing mechanism according to the order of contacting the object. The specific scenarios are as follows: Scenario a (the fingertip 63 touches first): As Figure 5 shown, when the object size is small or the object is located at a position slightly below the center of the clamping area 11, the fingertip 63 of the jaw assembly 60 touches the object surface first. At this time, blocked by the reaction force of the object, the hinge axis between the middle phalanx 62 and the fingertip 63 stops rotating, and the second elastomer 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 pulling of the drive rod 30 locks the hinge axis between the finger root 61 and the middle phalanx 62, resulting in the finger root 61 being unable to continue rotating. Finally, only the fingertip 63 clings to the object under the pulling force of the tension spring of the drive rod 30 to complete the grasping, and the grasping force is completely provided by the first elastomer 40, forming a stable single-point clamping.

[0028] Scenario b (the finger root 61 and the middle phalanx 62 are closed, and the fingertip 63 is suspended): As Figure 6 shown, when there are local depressions on the object surface or the grasping position is close to the base end of the jaw, the finger root 61 and the middle phalanx 62 may touch the object first. For example, when grasping a workpiece with a stepped structure, the finger root 61 touches the upper side of the workpiece and stops rotating due to the block. The continuous pulling force of the drive rod 30 forces the middle phalanx 62 to continue rotating around the hinge axis of the finger root 61. When the opening angle between the middle phalanx 62 and the finger root 61 changes from -5° to a positive angle, the second elastomer 41 between the two crosses the critical point, releases the stored energy and generates an additional closing force, causing the middle phalanx 62 to quickly press against the object surface. At the same time, due to the object contour blocking or insufficient clamping depth (such as the workpiece being relatively short) of the hinge axis between the middle phalanx 62 and the fingertip 63, the fingertip 63 cannot continue to rotate inward, and its opening angle always remains in a negative angle state. The second elastomer 41 does not trigger the critical point conversion, and the fingertip 63 is in a suspended and unclosed posture. In this scenario, the grasping action is completed by the cooperation of the finger root 61 and the middle phalanx 62, forming a two-point support grasping. The grasping force is jointly provided by the first elastomer 40 of the drive rod 30 and the second elastomer 41 between the finger root 61 and the middle phalanx 62, and is applicable to flat or stepped objects with relatively low requirements for grasping accuracy but requiring quick fixation.

[0029] Scenario c (the middle phalanx 62 touches first): As Figure 7As shown, if the height of the object is moderate and the grasping position is above the middle, the middle phalanx 62 will contact the object first. At this time, the hinge axis between the finger root 61 and the middle phalanx 62 is blocked, and the finger root 61 stops rotating. However, the pulling force of the driving 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 around their hinge axis until the opening angle between them changes from -5° to a positive angle, the second elastic body 41 between them crosses the critical point, and the elastic potential energy is instantly released and converted into an additional closing force, pushing the fingertip 63 to accelerate and press the object tightly. During this process, the finger root 61 remains stationary, and the middle phalanx 62 and the fingertip 63 cooperate to form a two-point envelope grasping, and the grasping force is provided jointly by the first elastic body 40 and the second elastic body 41.

[0030] Scenario d (the finger root 61 contacts first): When grasping a large-sized or high-position object, the finger root 61 contacts the object first. Due to the continuous downward pulling action of the driving rod 30, at this time, the middle phalanx 62 continues to rotate around its hinge axis with the finger root 61 until the opening angle between the middle phalanx 62 and the finger root 61 changes from -5° to a positive angle, and the second elastic body 41 between them crosses the critical point, releasing the stored energy and generating an additional closing force, causing the middle phalanx 62 to quickly press against the object surface. Then, since the middle phalanx 62 is fixed after contacting and rubbing against the object, under the continuous downward pulling action of the driving rod 30, the fingertip 63 continues to rotate around its hinge axis with the middle phalanx 62 until the opening angle between the middle phalanx 62 and the fingertip 63 changes from -5° to a positive angle, and the second elastic body 41 between them crosses the critical point, and the elastic potential energy is instantly released and converted into an additional closing force, pushing the fingertip 63 to accelerate and press the object tightly, forming an envelope grasping structure. Finally, the finger root 61, the middle phalanx 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 cooperative action of the three groups of elastic bodies.

[0031] It should be added that Figures 5 to 7 When the jaw assembly 60 of triggers grasping, in order to prevent the second elastic body 41 from contacting the object to be grasped, the thickness of the phalanx can be increased to avoid interference.

[0032] This device significantly improves the grasping efficiency and adaptability through the mechanical trigger and the step-by-step closing mechanism of the underactuated mechanism. Its core advantages are: Release the locking and release the elastic potential energy through pure mechanical linkage, eliminating the signal transmission and drive adjustment links of the traditional electronic control system. The grasping action is completed instantly at the moment of triggering, which is suitable for high-speed production line scenarios; Each phalanx locks or releases independently according to the contact sequence, and the dynamic superposition of the closing force is realized through the critical point switching of the second elastic body 41, which not only ensures the flexible grasping of the lightly touched object but also can provide a gradually increasing clamping force for the heavy-load object; A single drive rod 30 is used to synchronously control multiple groups of jaw assemblies 60. By adjusting the symmetrical or staggered layout of the jaws, it can adapt to objects of different shapes, and the number of joints can be expanded without adding drive elements. Each jaw assembly 60 operates independently. Even if the object shape is asymmetrical or the placement is offset, stable grasping can still be achieved through the closing of local knuckles, avoiding the overall out-of-control problem caused by the single-point failure of the traditional linkage mechanism.

[0033] Generally speaking, this solution realizes rapid triggering and adaptive grasping with a pure mechanical structure, taking into account grasping accuracy and reliability while simplifying the mechanism, and is particularly suitable for precision grasping scenarios such as electronic components and special-shaped workpieces.

[0034] As a preferred embodiment, the first elastic body 40 and the second elastic body 41 of this embodiment both use tension springs. Tension springs have the characteristics of compact structure, convenient installation, and obvious linear elastic characteristics. They can accurately control the critical point of energy storage and release, ensuring the rapid swing of the drive rod 30 and the instantaneity of the angle conversion between the knuckles. At the same time, the pre-tension of the tension spring can be adjusted flexibly, and different grasping force requirements can be matched by adjusting the installation position or the wire diameter of the spring. Moreover, it has low cost and high reliability, and is suitable for batch applications in industrial scenarios.

[0035] It should be noted that the tension spring is only a preferred embodiment of the elastic body. In other embodiments, those skilled in the art can choose an equivalent elastic element to replace it according to actual needs. For example: Elastic ropes, silicone elastomers and other materials can also be used to achieve non-linear elastic characteristics. Simple modifications or combined applications of the above elastic elements, as long as they can achieve the technical effects of energy storage triggering, critical point locking, and adaptive grasping, are within the protection scope of the claims of this application.

[0036] Further, please refer to Figures 1 to 4, the trigger 20 includes a push switch 21 that can be triggered by an object and a push rod 22 linked to the push switch 21. The locking mechanism 50 includes two hanging rods 51 hinged at the top to the carrier 10 and an elastic reset member connecting the two hanging rods 51. A wedge-shaped inclined plane 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 plane 52 to release the drive 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 applied by the object forces the push switch 21 to move upward. Under the action of the connecting rod, the push rod 22 is laterally inserted into the wedge-shaped inclined plane 52 between the two hanging rods 51 of the locking mechanism 50. By sliding and squeezing the inclined plane, the two hanging rods 51 are forced to separate outward against the pulling force of the elastic reset member, thereby releasing the locking constraint on the drive rod 30. This pure mechanical linkage trigger mechanism does not require external energy or electronic control signals to intervene. The locking and release actions are completed instantly when the object comes into contact, achieving a millisecond-level response, and completely avoiding the risk of grasping failure caused by signal transmission and processing delays in traditional electronic control sensing systems. At the same time, the modular design of the push switch 21 and the push rod 22 makes it highly robust, capable of working stably in harsh industrial environments such as dust and oil stains, and the maintenance cost is significantly lower than that of hydraulic or pneumatic trigger devices.

[0037] As Figure 2 shown, a rotational limit structure 70 is provided between two adjacent phalanges to limit their maximum negative angle. The rotational limit structure 70 includes a limit blocking surface 71 provided on the phalanx and a limit boss 72 provided on the adjacent phalanx. When the phalanx rotates to the maximum negative angle, the limit blocking surface 71 abuts against the limit boss 72, and the maximum negative angle is R, where R = -5°. The specific action is as follows: When the phalanges (such as the middle phalanx 62 and the fingertip 63) are in the initial open state, the limit blocking surface 71 at the end of the fingertip 63 tightly abuts against the limit boss 72 at the base of the middle phalanx 62, forming a rigid block to prevent the fingertip 63 from further opening in the reverse direction. This design ensures that the pre-tightening force of the second elastic body 41 is in the optimal energy storage range by precisely controlling the negative angle range, avoiding elastic failure caused by excessive spring stretching and providing sufficient potential energy reserve for the angle to turn from negative to positive when triggering the closure.

[0038] Please refer to Figure 3 , the jaw assembly 60 further includes a link assembly 80. The link assembly 80 includes a first link 81 hinged to the middle phalanx 62, a second link 82 hinged to the fingertip 63, and the first link 81 and the second link 82 are hinged to each other. The link assembly 80 further includes a third link 83. One end of the third link 83 is hinged to the drive rod 30, and the other end is hinged to the adjacent first link 81.

[0039] The connecting rod assembly 80 realizes the motion coupling between the driving rod 30 and each finger joint through a multi-stage hinge structure: when the driving rod 30 is driven by the first elastic body 40 to swing downward, 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, and at the same time, the hinge point of the first connecting rod 81 and the second connecting rod 82 transmits the torque to the fingertip 63, driving it to close synchronously; if a finger joint is blocked from contacting an object, the pulling force of the driving 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 the coordination of the rigid connecting rod and the elastic body accurately limits the swing angle of the finger joint through the four-bar mechanism, not only realizing the synchronous drive of multiple joints with fewer parts, avoiding the motion disorder problem of the pure elastic body system, but also expanding the number of finger joints by adding connecting rod modules. Compared with the traditional multi-stage transmission structure, it can reduce the number of parts, and significantly improve the grasping stability and assembly efficiency while ensuring the under-driven adaptive characteristics.

[0040] As a preferred embodiment, Figure 1 As 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 finger tip 63 of this embodiment); the motor 91 drives the reel 92 to rotate and reel in, and pulls each finger joint 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 can be used to drive the reel 92 to rotate and reel in, and the pull rope 93 can be 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 be fixed by the locking mechanism 50, ensuring that the entire mechanism is automatically and completely reset to the waiting trigger state without manual reset.

[0041] In addition, in order to make the driving rod 30 easier to reset and ensure that it is reliably locked by the locking mechanism 50 after reset, as shown in FIG. Figure 4 As shown, in this embodiment, two guiding inclined surfaces 53 are added at the bottom of the two hanging rods 51 to form an eight-shaped guiding structure. When the motor 91 drives the winding disk 92 to collect the rope and pull the clamping claw assembly 60, the clamping claw assembly 60 drives the driving rod 30 to slide upward along the eight-shaped guiding structure, and this process gradually opens the two hanging rods 51, and finally the driving rod 30 is smoothly inserted into the locking groove between the two hanging rods 51; then, under the pulling force of the elastic reset member, the two hanging rods 51 are reset and closed, locking the driving rod 30.

[0042] The above has specifically described the preferred embodiments of the present invention. However, the present invention is not limited to the described embodiments. Those skilled in the art can also make various equivalent variations or substitutions without departing from the spirit of the present invention. These equivalent variations or substitutions are all included within the scope defined by the claims of the present invention.

Claims

1. A trigger-type fast-grasping underactuated finger mechanism, characterized in that, include: A carrier (10) having a clamping area (11) disposed below the carrier; A trigger (20) is disposed 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 the initial position is fixed by a locking mechanism (50); the trigger (20) is linked to control the opening and closing of the locking mechanism (50); 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) to form an energy storage state with a negative opening angle; when an 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 achieve adaptive closing of the remaining finger joints; The reset assembly (90) is used to drive the drive 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 of the clamping jaw assemblies (60) and their knuckles to reset to the initial open state.

2. The trigger - type fast - grasping under - actuated finger mechanism according to claim 1, wherein The trigger (20) comprises a push switch (21) that can be triggered by an object, and a push rod (22) that is linked to the push switch (21); the push rod (22) is mechanically linked to a locking mechanism (50).

3. The trigger - type fast - grasping under - actuated finger mechanism according to claim 2, wherein, 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).

4. The trigger - type fast - grasping under - actuated finger mechanism according to claim 1, characterized in that, A rotation limiting structure (70) is provided between two adjacent finger joints, for limiting the maximum negative angle between the two.

5. A trigger-type fast grasping underactuated finger mechanism according to claim 4, 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).

6. The trigger - type fast - grasping under - actuated finger mechanism according to claim 4, wherein, The maximum negative angle is -5°.

7. A trigger-type quick-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.

8. A trigger-type fast-gripping 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.

9. The trigger - type fast - grasping under - actuated finger mechanism according to claim 8, wherein, The link assembly (80) further includes a third link (83), one end of the third link (83) is hinged to the drive rod (30), and the other end is hinged to the adjacent first link (81).

10. A trigger-type fast-gripping underactuated finger mechanism according to claim 1, characterized in that, The reset assembly (90) includes: a motor (91) fixed to the vehicle (10); a winding disc (92) mounted on the output shaft of the motor (91); and a pulling rope (93) wound around the winding disc (92); wherein, the distal end of the pulling rope (93) is connected to the end of the finger joint farthest from the trigger (20); By driving the winding disc (92) to rotate and wind the rope by the motor (91), the respective finger joints of the jaw assembly (60) are pulled to expand outwards synchronously until all the jaw assemblies (60) are reset to the initial open state.

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