A symmetrical linkage electric gripper and robot

Abstract

This application provides a symmetrical linkage-type electric gripper and robot, belonging to the field of electric actuator technology. The symmetrical linkage-type electric gripper includes: a slide rail structure mounted on a base, with two grippers slidably mounted on the slide rail structure; and a linkage transmission assembly including a rotating disk, a rotating rod, two first connecting rods, and two second connecting rods. The rotating disk is connected to the output shaft of a drive motor, and the center of the rotating disk is hinged to the center of the rotating rod. Two protruding rods are provided on the circumferential edge of the rotating disk. The rotating rod, the two first connecting rods, the two second connecting rods, and the two protruding rods form two rhomboid transmission structures. The rhomboid contours of the two rhomboid transmission structures are symmetrically arranged in the relative movement direction of the grippers. This application enables more symmetrical transmission force, which helps eliminate off-center loading, ensures high precision of the gripping surface, improves gripping stability, increases the lifespan and overall load-bearing capacity of the electric gripper, and improves the overall structural rigidity while maintaining low cost.

Description

Technical Field

[0001] This application relates to the field of electric actuator technology, and in particular to a symmetrical linkage electric gripper and robot. Background Technology

[0002] With the rapid development of industrial automation and intelligent manufacturing technologies, industrial robots and collaborative robots have been widely used in industrial automated production and home services. As the core actuator of the robot's end effector, the electric gripper's gripping accuracy, response speed, and structural compactness directly determine the efficiency and reliability of the operation. Among them, the parallel opening and closing electric gripper is the most widely used type of gripper.

[0003] In related technologies, parallel electric grippers mainly adopt the following transmission schemes: First, the screw and nut transmission scheme, which uses a motor to drive the forward and reverse screws to rotate, causing the nut seats on both sides and the grippers to open and close synchronously along the slide rail; Second, the gear and rack transmission scheme, which uses a motor to drive the gears to rotate, causing the meshing racks on both sides to move in opposite directions, thus realizing the parallel opening and closing of the grippers; Third, the crank and connecting rod transmission scheme, which uses a motor to drive the crank to rotate, causing the single-sided connecting rod mechanism to push and pull the grippers along the slide rail, relying on the force amplification effect of the connecting rod to achieve a large clamping force.

[0004] However, the lead screw and nut drive system has inherent backlash. After long-term high-frequency operation, wear on the lead screw and nut will further widen the backlash, leading to a decrease in clamping repeatability and positioning accuracy. Furthermore, the lead screw drive has a large axial dimension, which is detrimental to the compact design of the grippers. The gear and rack drive system requires high precision in gear machining and assembly, resulting in higher manufacturing costs. Moreover, the impact on the gear teeth during high-speed start-stop is significant, easily generating noise and tooth surface wear. Conventional crank-connecting rod drive systems are mostly single-sided drive or asymmetrical layouts. Uneven force distribution on the grippers during operation easily leads to off-center loading, causing the gripper clamping surface to tilt and experience slight displacement, resulting in low clamping accuracy and poor stability. In addition, unilateral force distribution leads to uneven wear of the slide rails, severely affecting the lifespan and overall load-bearing capacity of the electric grippers. Summary of the Invention

[0005] This application provides a symmetrical linkage-type electric gripper and robot, which enables more symmetrical transmission force, helps eliminate off-center loading, ensures high precision of the gripping surface, improves gripping stability, and increases the lifespan and overall load-bearing capacity of the electric gripper. It also improves the overall structural rigidity while maintaining low cost. The technical solution includes at least the following: On one hand, a symmetrical linkage-type electric gripper is provided, comprising: a base; a drive motor disposed at the bottom of the base and located at the center of the base; a slide rail structure disposed on the base, on which two grippers are slidably disposed; and a linkage transmission assembly comprising a rotating disk, a rotating rod, two first connecting rods, and two second connecting rods. The rotating disk is connected to the output shaft of the drive motor, the center of the rotating disk is hinged to the center of the rotating rod, and two protruding rods are provided on the circumferential edge of the rotating disk. The protruding rods are hinged to the first ends of the first connecting rods, and the second ends of the first connecting rods are hinged to the first ends of the second connecting rods and connected to the corresponding grippers. The two ends of the rotating rod are respectively hinged to the second ends of the two second connecting rods. The rotating rod, the two first connecting rods, the two second connecting rods, and the two protruding rods form two rhomboid transmission structures. The drive motor is used to drive the rotating disk to rotate so that the two grippers move closer to each other or further away from each other. The rhomboid contours of the two rhomboid transmission structures are symmetrically arranged in the relative movement direction of the grippers.

[0006] Optionally, thrust bearings are provided at the hinge points of the rotating rod and the rotating disk, the hinge points of the protruding rod and the first connecting rod, the hinge points of the first connecting rod and the second connecting rod, the hinge points of the second connecting rod and the rotating rod, and the connection points of the first connecting rod and the gripper.

[0007] Optionally, the slide rail structure includes two slide rails, which are arranged parallel to each other on the top of the base. The orthographic projections of the two slide rails on the base are located on both sides of the center of the rotating disk and are symmetrically arranged. Each slide rail has two sliders that are respectively connected to the two grippers. The connection between the first connecting rod and the gripper is located between the two slide rails.

[0008] Optionally, the base includes a base plate and four abutment structures spaced apart on the base plate. Each abutment structure includes an abutment post and a support platform. The top of the abutment post has a groove, and the two ends of the slide rail are respectively disposed in the corresponding grooves. The support platform is located between the base plate and the slide rail and is connected to the abutment post.

[0009] Optionally, an elastic buffer pad is provided on the side of the abutment post near the slider.

[0010] Optionally, the base plate has a through hole at its center, the rotating disk is located in the through hole, the rotating rod, the first connecting rod and the second connecting rod are all located between the base plate and the slide rail structure, and the drive motor is located on the side of the base plate away from the rotating disk and is fixedly connected to the rotating disk.

[0011] Optionally, the maximum stroke of the two grippers in the relative motion direction is 60 mm to 100 mm.

[0012] Optionally, multiple anti-slip grooves are provided on the clamping surfaces of both grippers.

[0013] Optionally, the drive motor is a servo motor or a stepper motor.

[0014] On the other hand, a robot is provided, including a robotic arm and the aforementioned symmetrical linkage electric gripper, the symmetrical linkage electric gripper being disposed at the execution end of the robotic arm.

[0015] The beneficial effects of the technical solution provided in this application include at least the following: In this embodiment, the linkage transmission assembly includes a rotating disk, a rotating rod, two first connecting rods, and two second connecting rods. The rotating disk is connected to the output shaft of a drive motor. The center of the rotating disk is hinged to the center of the rotating rod. Two protruding rods are provided on the circumferential edge of the rotating disk. The rotating rod, the two first connecting rods, the two second connecting rods, and the two protruding rods form two rhomboid transmission structures. The rhomboid contours of the two rhomboid transmission structures are symmetrically arranged in the relative movement direction of the grippers. By forming two symmetrical rhomboid transmission structures, during the process of the drive motor driving the rotating disk to rotate and causing the two grippers to move relative to each other, the transmission force of the linkage transmission assembly can be made more symmetrical, and the horizontal force of the linkage transmission assembly can be more uniform. This helps to eliminate off-center loads, ensure high precision of the clamping surface, improve clamping stability, and the double-sided force transmission of the rhomboid transmission structure can ensure that the force on the slide rail structure is more uniform during the sliding process, thereby reducing the probability of wear on the slide rail structure and improving the life of the electric gripper and the overall load-bearing capacity. In addition, the two rhomboid transmission structures share a central rotating disk and rotating rod, resulting in a shorter overall transmission chain and higher force transmission efficiency. This can improve the overall structural rigidity of the electric gripper while ensuring low assembly costs, and the deformation of the electric gripper is small under large clamping forces. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of a symmetrical linkage electric gripper provided in an embodiment of this application.

[0018] Figure 2 This is a schematic diagram of the linkage transmission assembly provided in the embodiments of this application.

[0019] Figure 3 This is a schematic diagram of the structure of the base provided in the embodiment of this application.

[0020] Figure 4 This is a schematic diagram of the extreme position of the symmetrical linkage electric gripper provided in the embodiment of this application in the relaxed state.

[0021] Figure 5 This is a schematic diagram of the extreme positions of the symmetrical linkage electric gripper provided in the embodiment of this application in the clamping state.

[0022] Figure label: 1: Base; 10: Base plate; 101: Through hole; 11: Abutment structure; 111: Abutment post; 112: Support platform; 2: Drive motor; 3: Gripper; 30: Anti-slip groove; 4: Slide rail structure; 40: Slide rail; 41: Slider; 5: Linkage transmission assembly; 50: Rotary disk; 51: Rotating rod; 52: First link; 53: Second link; 54: Protruding rod; 55: Thrust bearing. Detailed Implementation

[0023] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms “first,” “second,” “third,” and similar terms used in this patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an” or “a” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “comprising” or “including” and similar terms mean that the element or object preceding “comprising” or “including” encompasses the element or object listed following “comprising” or “including” and its equivalents, and do not exclude other elements or objects. The terms “connected” or “linked” and similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms “upper,” “lower,” “left,” “right,” etc., are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0024] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0025] Figure 1 This is a schematic diagram of a symmetrical linkage electric gripper provided in an embodiment of this application. Figure 2 This is a schematic diagram of the linkage transmission assembly provided in an embodiment of this application. See also... Figure 1 and Figure 2The symmetrical linkage electric gripper includes: a base 1; a drive motor 2, located at the bottom and center of the base 1; a slide rail structure 4, mounted on the base 1, with two grippers 3 slidably mounted on the slide rail structure 4; and a linkage transmission assembly 5, including a rotating disk 50, a rotating rod 51, two first connecting rods 52, and two second connecting rods 53. The rotating disk 50 is connected to the output shaft of the drive motor 2, and the center of the rotating disk 50 is hinged to the center of the rotating rod 51. Two protruding rods 54 are provided on the circumferential edge of the rotating disk 50. The first end of the first connecting rod 52 is hinged to the first end of the second connecting rod 53 and connected to the corresponding gripper 3. The two ends of the rotating rod 51 are respectively hinged to the second ends of the two second connecting rods 53. The rotating rod 51, the two first connecting rods 52, the two second connecting rods 53 and the two protruding rods 54 form two rhomboid transmission structures. The drive motor 2 is used to drive the rotating disk 50 to rotate so that the two grippers 3 move closer or further away from each other. The rhomboid contours of the two rhomboid transmission structures are symmetrically arranged in the relative movement direction of the grippers 3.

[0026] In this embodiment, the linkage transmission assembly 5 includes a rotating disk 50, a rotating rod 51, two first connecting rods 52, and two second connecting rods 53. The rotating disk 50 is connected to the output shaft of the drive motor 2. The center of the rotating disk 50 is hinged to the center of the rotating rod 51. Two protruding rods 54 are provided on the circumferential edge of the rotating disk 50. The rotating rod 51, the two first connecting rods 52, the two second connecting rods 53, and the two protruding rods 54 form two rhomboid transmission structures. The rhomboid contours of the two rhomboid transmission structures are symmetrically arranged in the relative movement direction of the grippers 3. By forming two symmetrical rhomboid transmission structures, during the process of the drive motor 2 driving the rotating disk 50 to rotate so that the two grippers 3 generate relative movement, the transmission force of the linkage transmission assembly 5 can be made more symmetrical, and the horizontal force of the linkage transmission assembly 5 can be more uniform. This is beneficial for eliminating off-center loads, ensuring high precision of the clamping surface, improving clamping stability, and the double-sided force transmission of the rhomboid transmission structure can ensure that the force on the slide rail structure 4 is more uniform during the sliding process, thereby reducing the probability of wear on the slide rail structure 4 and improving the life of the electric gripper and the overall load-bearing capacity. In addition, the two rhomboid transmission structures share a central rotating disk 50 and rotating rod 51, resulting in a shorter overall transmission chain and higher force transmission efficiency. This can improve the overall structural rigidity of the electric gripper while ensuring a lower assembly cost, and the electric gripper exhibits smaller deformation under greater clamping force.

[0027] It should be noted that the rhombus outline of the rhombus transmission structure refers to the shape formed by sequentially connecting the hinge points of the rotating rod 51 and the rotating disk 50, the hinge points of the protruding rod 54 and the first connecting rod 52, the hinge points of the first connecting rod 52 and the second connecting rod 53, and the hinge points of the second connecting rod 53 and the rotating rod 51 from a top-down view. In this embodiment, the rhombus outlines of the two rhombus transmission structures are arranged symmetrically from left to right, and the two rhombus transmission structures are centrally symmetrical about the center of the rotating disk 50.

[0028] In this embodiment, multiple anti-slip grooves 30 are provided on the clamping surfaces of both grippers 3. By setting the anti-slip grooves 30, the friction during clamping can be increased, which is beneficial for the stable clamping of irregular and eccentric objects, achieving non-slip and non-deformation, thus adapting to a wider range of clamping scenarios.

[0029] For example, thrust bearings 55 are provided at the hinges of the rotating rod 51 and the rotating disk 50, the hinges of the protruding rod 54 and the first connecting rod 52, the hinges of the first connecting rod 52 and the second connecting rod 53, the hinges of the second connecting rod 53 and the rotating rod 51, and the connection between the first connecting rod 52 and the gripper 3. By providing thrust bearings 55, the friction at each hinge and connection can be reduced, thereby reducing wear and improving the service life and reliability of the electric gripper. At the same time, the thrust bearings 55 at the hinges of the rotating rod 51 and the rotating disk 50 ensure that the driving action of the drive motor 2 on the rotating disk 50 does not affect the rotation of the rotating rod 51. When the two grippers 3 approach or move away from each other, the rotation directions of the rotating disk 50 and the rotating rod 51 are opposite. For example, when the drive motor 2 drives the rotating disk 50 to rotate counterclockwise, the force is transmitted through the two symmetrical rhomboid transmission structures, the rotating rod 51 rotates clockwise, and the two grippers 3 move away from each other so that the electric grippers relax; conversely, when the drive motor 2 drives the rotating disk 50 to rotate clockwise, the force is transmitted through the two symmetrical rhomboid transmission structures, the rotating rod 51 rotates counterclockwise, and the two grippers 3 move closer to each other so that the electric grippers clamp.

[0030] Optionally, the slide rail structure 4 includes two slide rails 40, which are arranged parallel to each other on the top of the base 1. The orthographic projections of the two slide rails 40 on the base 1 are located on both sides of the center of the rotating disk 50 and are symmetrically arranged. Each slide rail 40 has two sliders 41 that are respectively connected to the two grippers 3. The connection between the first connecting rod 52 and the gripper 3 is located between the two slide rails 40. By symmetrically arranging the double slide rails and cooperating with the connecting rod transmission assembly 5, the uniformity of force on the slide rail structure 4 when the two grippers 3 move relative to each other can be further improved, thereby greatly improving the clamping stability and load-bearing capacity, further improving the clamping accuracy, and effectively offsetting the lateral component force. The drive motor 2 can be driven without complex algorithms to compensate for the off-center load error, which can reduce the requirements for precise force control of the motor and reduce control costs. For example, the drive motor 2 can be a servo motor or a stepper motor. In this embodiment, the gripper 3 is fixedly connected to the slider 41 by bolts.

[0031] Figure 3 This is a schematic diagram of the structure of the base provided in an embodiment of this application. See also... Figures 1 to 3 For example, the base 1 includes a base plate 10 and four abutment structures 11 spaced apart on the base plate 10. Each abutment structure 11 includes an abutment post 111 and a support platform 112. The top of the abutment post 111 has a groove, and the two ends of the slide rail 40 are respectively disposed in the corresponding grooves. The support platform 112 is located between the base plate 10 and the slide rail 40 and is connected to the abutment post 111. By providing the abutment structure 11, not only can the gripper 3 be abutted at its extreme opening position, but the slide rail 40 can also be better supported, which is beneficial to improving the stability of the electric gripper. In this embodiment, the slide rail 40 can be fixedly connected to the support platform 112 by bolts.

[0032] In one possible implementation, the slide rail structure 4 may also include only one slide rail 40, with two sliders 41 respectively connected to the two grippers 3 on the single slide rail 40. The hinge point of the first connecting rod 52 and the second connecting rod 53 may be located directly below the single slide rail 40, and the second end of the first connecting rod 52 is connected to the slider 41. This application does not limit this. Even with a single slide rail 40, the transmission force can still be more symmetrical through the linkage transmission assembly 5, and the wear of the slide rail 40 can be reduced compared to the traditional single-sided linkage transmission. Compared with a single slide rail, the double slide rail not only effectively improves the uniformity of force on the slide rail structure 4, but also reduces the vertical distance between the slide rail structure 4 and the linkage transmission assembly 5, reducing the device volume of the electric gripper and improving stability.

[0033] Optionally, an elastic buffer pad (not shown) is provided on the side of the abutment post 111 near the slider 41. By providing an elastic buffer pad, the slider 41 can be buffered when the electric gripper opens to its limit position, thereby reducing the probability of collision damage to the slider 41 and improving its service life.

[0034] For example, a through hole 101 is provided at the center of the base plate 10, the rotating disk 50 is located in the through hole 101, the rotating rod 51, the first connecting rod 52 and the second connecting rod 53 are all located between the base plate 10 and the slide rail structure 4, and the drive motor 2 is located on the side of the base plate 10 away from the rotating disk 50 and is fixedly connected to the rotating disk 50. In this embodiment, the drive motor 2 can be fixedly connected to the base plate 10 by bolts.

[0035] Figure 4 This is a schematic diagram of the extreme position of the symmetrical linkage electric gripper provided in the embodiment of this application in the relaxed state. Figure 5 This is a schematic diagram showing the extreme positions of the symmetrical linkage-type electric gripper provided in the embodiment of this application in the clamping state. See also... Figure 4 and Figure 5 When the two grippers 3 are far apart and in their relaxed extreme positions, the distance between the connection points of the two grippers 3 and the corresponding first link 52 is L1. When the two grippers 3 are close together and in their clamping extreme positions, the distance between the connection points of the two grippers 3 and the corresponding first link 52 is L2. Optionally, the maximum stroke of the two grippers 3 in the relative motion direction is 60mm to 100mm. Here, the maximum stroke refers to the maximum distance that the two grippers 3 can move between their extreme positions when they are close together and in a clamping state and their extreme positions when they are far apart and in a relaxed state, i.e., L1-L2. L1-L2 can be 60mm to 100mm. This can better meet the fine gripping needs of home services, while also being adaptable to large-stroke clamping in industrial scenarios, making it highly versatile.

[0036] For example, the maximum stroke of the two grippers 3 in the relative motion direction can be 60mm, 80mm, or 100mm, etc. In this embodiment, L1 can be 100mm, L2 can be 20mm, and the maximum stroke L1-L2 of the two grippers 3 in the relative motion direction can be 80mm, that is, the two grippers 3 can move relative to each other within the stroke range of 0mm to 80mm.

[0037] It should be noted that the maximum stroke range of the two grippers 3 in the relative motion direction is only an example. In other embodiments, the clamping stroke can also be flexibly adjusted to meet different clamping requirements by changing the length of the rotating rod 51, the first connecting rod 52, the second connecting rod 53, and the protruding rod 54, that is, by changing the side length of the rhombus contour of the rhombus transmission structure. This application does not limit this.

[0038] This application also provides a robot, including a robotic arm and the aforementioned symmetrical linkage electric gripper, wherein the symmetrical linkage electric gripper is disposed at the execution end of the robotic arm.

[0039] The above description is merely an optional embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A symmetrical linkage type electric gripper, characterized in that, include: Base; A drive motor is located at the bottom of the base and at the center of the base; A slide rail structure is provided on the base, and two grippers are slidably disposed on the slide rail structure; A linkage transmission assembly includes a rotating disk, a rotating rod, two first connecting rods, and two second connecting rods. The rotating disk is connected to the output shaft of the drive motor. The center of the rotating disk is hinged to the center of the rotating rod. Two protruding rods are provided on the circumferential edge of the rotating disk. The protruding rods are hinged to the first ends of the first connecting rods. The second ends of the first connecting rods are hinged to the first ends of the second connecting rods and connected to corresponding grippers. The two ends of the rotating rod are respectively hinged to the second ends of the two second connecting rods. The rotating rod, the two first connecting rods, the two second connecting rods, and the two protruding rods form two rhomboid transmission structures. The drive motor is used to drive the rotating disk to rotate so that the two grippers move closer to or further away from each other. The rhomboid contours of the two rhomboid transmission structures are symmetrically arranged in the relative movement direction of the grippers.

2. The symmetrical linkage electric gripper according to claim 1, characterized in that, Thrust bearings are provided at the hinge points of the rotating rod and the rotating disk, the hinge points of the protruding rod and the first connecting rod, the hinge points of the first connecting rod and the second connecting rod, the hinge points of the second connecting rod and the rotating rod, and the connection points of the first connecting rod and the gripper.

3. The symmetrical linkage electric gripper according to claim 1, characterized in that, The slide rail structure includes two slide rails, which are arranged parallel to each other on the top of the base. The orthographic projections of the two slide rails on the base are located on both sides of the center of the rotating disk and are symmetrically arranged. Each slide rail has two sliders that are respectively connected to the two grippers. The connection point between the first connecting rod and the gripper is located between the two slide rails.

4. The symmetrical linkage electric gripper according to claim 3, characterized in that, The base includes a base plate and four abutment structures spaced apart on the base plate. Each abutment structure includes an abutment post and a support platform. The top of the abutment post has a groove, and the two ends of the slide rail are respectively disposed in the corresponding grooves. The support platform is located between the base plate and the slide rail and is connected to the abutment post.

5. The symmetrical linkage electric gripper according to claim 4, characterized in that, An elastic buffer pad is provided on the side of the abutment post closest to the slider.

6. The symmetrical linkage electric gripper according to claim 4, characterized in that, The base plate has a through hole at its center, the rotating disk is located in the through hole, the rotating rod, the first connecting rod and the second connecting rod are all located between the base plate and the slide rail structure, and the drive motor is located on the side of the base plate away from the rotating disk and is fixedly connected to the rotating disk.

7. The symmetrical linkage electric gripper according to any one of claims 1 to 6, characterized in that, The maximum stroke of the two grippers in the relative motion direction is 60 mm to 100 mm.

8. The symmetrical linkage electric gripper according to any one of claims 1 to 6, characterized in that, Multiple anti-slip grooves are provided on the clamping surfaces of both grippers.

9. The symmetrical linkage electric gripper according to any one of claims 1 to 6, characterized in that, The drive motor is a servo motor or a stepper motor.

10. A robot, characterized in that, The invention includes a robotic arm and a symmetrical linkage electric gripper as described in any one of claims 1 to 9, wherein the symmetrical linkage electric gripper is disposed at the execution end of the robotic arm.

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