Robot and mechanical gripper thereof

Abstract

The present application provides a mechanical gripper. The mechanical gripper comprises a driving assembly comprising a driving rod; a moving assembly, coupled with the driving rod and driven by the driving rod to move in the axis direction of the driving rod; and a gripper assembly, connected to the moving assembly and comprising a plurality of fingers, wherein the moving assembly drives the plurality of fingers to get close to or move away from each other during moving in the axis direction. The mechanical gripper in the present application has good sealing capacity, eccentric load capacity, and power-off self-locking capacity. In addition, the present application further achieves control over a real-time opening / closing stroke and opening / closing speed of the mechanical gripper, and has the advantages such as a strong clamping force, small size, light weight, low cost, and simple manipulation. The present application further provides a robot.

Description

Robot and mechanical gripper thereof

[0001] REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the prior application for invention patent filed in China on April 12, 2024, with the application number 202410446762.8, and the invention name "Robot and mechanical gripper thereof", the entire contents of the prior application are incorporated herein by reference. TECHNICAL FIELD

[0003] The present application relates to the technical field of robot end grasping, in particular, to a robot and a mechanical gripper thereof. BACKGROUND

[0004] With the development of artificial intelligence, the puzzle of robots moving from industrial scenes to commercial scenes is becoming more and more complete, which makes the market demand for robots and their mechanical grippers higher and higher.

[0005] At present, home scenes and service scenes have become the first choice for civilian robots to land. However, the complexity of real scenes makes the application of robots face great challenges, and the mechanical gripper of the robot, as the main part of contact and interaction with environmental objects, faces the most risks and challenges.

[0006] For example, in the kitchen scene, the robot and its mechanical gripper face the following challenges: first, it needs to have the ability to bear a large central load or even eccentric load. Because the commonly used kitchen utensils are in contact with heat sources, they are usually provided with a relatively long handle for heat dissipation, such as frying pans, frying baskets, etc., which makes the mechanical gripper need to resist a torque of 8-9 N · m or even more when grasping. The existing connecting rod type gripper usually cannot resist more than 6 N · m of eccentric torque, which is far from meeting the actual needs. Second, high temperature, water vapor, contact with liquid and other complex working conditions as well as food hygiene and safety all require the sealing performance of the mechanical gripper, and the prior art has not made special design for such sealing performance of the mechanical gripper. Third, the diversity of kitchen items, objects with different shapes and weights, on the one hand, require the clamping force of the gripper, and on the other hand, also challenge the generalization ability of the gripper to grasp objects. Fourth, in the case of sudden power failure of the robot during grasping, the mechanical gripper needs to be locked immediately to avoid the danger of falling of the grasped object.

[0007] The existing connecting rod type gripper, self-adaptive type gripper, etc. cannot meet the requirements of sealing performance, clamping force, generalization clamping, eccentric load and power failure self-locking, and often cannot perform the tasks in human life scenes; the robot dexterous hand is difficult to truly commercialize due to high cost and complex control.

[0008] It should be understood that the description of the background art neither places the present application into the state of the art nor is it considered to be prior art to the present application.

[0009] SUMMARY

[0010] In one aspect, the present application provides a mechanical gripper, comprising: a driving assembly comprising a driving rod; a moving assembly coupled with the driving rod and moving along an axial direction of the driving rod; and a gripper assembly connected with the moving assembly and comprising a plurality of fingers, the moving assembly driving the plurality of fingers to approach or move away from each other during the moving along the axial direction.

[0011] In one embodiment, the mechanical gripper further comprises: a housing covering the outside of the driving assembly and the moving assembly; and a first sealing member located at a side of the housing away from the driving assembly and in contact with the gripper assembly to form a seal.

[0012] In one embodiment, the gripper assembly further comprises: a first support member penetrating through the housing and comprising a first support member first part and a first support member second part, the first support member first part having a larger radial dimension than the first support member second part, and the first support member second part being located at a side of the housing away from the driving assembly, the first sealing member being sleeved on the first support member.

[0013] In one embodiment, the gripper assembly further comprises: a first connecting member having one end connected with the first support member second part and the other end connected with the fingers for driving the movement of the fingers; and a transverse connecting member having one end connected with the moving assembly and the other end connected with the first support member first part for driving the rotation of the first support member, wherein the first support member and the end of the first connecting member rotate together, and the end of the first connecting member is in contact with the first sealing member.

[0014] In one embodiment, the gripper assembly further comprises: a second support member penetrating through the housing and comprising a second support member first part and a second support member second part, wherein the second support member second part is located at a side of the housing away from the driving assembly, and the first sealing member is sleeved on the second support member; and a second connecting member having one end connected with the second support member second part and the other end connected with the fingers, wherein during the approaching or moving away of the plurality of fingers, the first connecting member and the second connecting member remain parallel to each other so that the angle of the plurality of fingers relative to the axial direction remains unchanged, and the end of the second connecting member is in contact with the first sealing member.

[0015] In one embodiment, the mechanical gripper further comprises a signal acquisition unit configured to record rotation information of the driving rod; and a control unit configured to perform motion planning based on the rotation information of the driving rod to control the real-time opening and closing amount of the plurality of fingers.

[0016] In one embodiment, the mechanical gripper further comprises a sensor configured to feed back to the control unit a signal of movement of the movable assembly to a zero position and a target position to control the maximum opening and closing amount of the plurality of fingers, wherein the target position corresponds to the maximum opening and closing amount of the plurality of fingers.

[0017] In one embodiment, the driving assembly comprises a driver, and the housing comprises a limiting block located on a side of the driver close to the movable assembly to limit the movement of the transverse connecting member along the axis direction, wherein the driver drives the driving rod to rotate to drive the movable assembly to move along the axis direction when powered on, and locks the rotation of the driving rod to limit the movement of the movable assembly when powered off.

[0018] In one embodiment, the first connecting member comprises a first connecting rod located on one side of the housing, a second connecting rod located on the other side of the housing opposite to the first connecting rod, and a web plate having one end connected to the first connecting rod and the other end connected to the second connecting rod.

[0019] In one embodiment, the driving rod comprises a threaded rod, the movable assembly comprises a threaded sleeve, and the coupling comprises a threaded fit formed by the threaded rod and the threaded sleeve.

[0020] In one embodiment, the fingers comprise recesses, and the recesses form a clamping space during the approach of the plurality of fingers to each other, wherein the recesses extend along an axial direction parallel to the first support member.

[0021] In one embodiment, the mechanical gripper further comprises a sealing bearing installed on the housing and sleeved on a surface of the first part of the first support member, wherein a first surface of the sealing bearing is in contact with the first sealing member.

[0022] In one embodiment, the mechanical gripper further comprises a second sealing member located on a side of the sealing bearing away from the first sealing member and in contact with a second surface of the sealing bearing and the first support member, respectively.

[0023] In one embodiment, the housing has a first space and a second space, the driver and the control unit are located in the first space, the movable assembly, the first support first part and the transverse connecting piece are located in the second space, and the second space is filled with a filler.

[0024] In one embodiment, the material of the housing comprises at least one of metal aluminum, aluminum alloy, stainless steel, metal titanium and carbon fiber, the material of the first seal comprises at least one of graphite, carbon fiber, polytetrafluoroethylene, polyoxymethylene thermoplastic polymer and semi-metal material, and the material of the first connecting rod comprises at least one of stainless steel and metal titanium.

[0025] Another aspect of the present application provides a robot, comprising: the mechanical gripper in any of the above embodiments; a mechanical arm; and a controller, which is in communication connection with the mechanical arm and the mechanical gripper, and is used to send instructions to control the movement of the mechanical arm and the opening and closing of the plurality of fingers, wherein the mechanical arm drives the movement of the mechanical gripper.

[0026] The features and advantages of the embodiments of the present application will be set forth in the following specification, and in part will be apparent from the specification, or can be learned by practice of the application. The purposes and other advantages of the embodiments of the present application will be realized and attained by the structure particularly pointed out in the specification and claims of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0027] Other features, objects and advantages of the present application will become more apparent from the following detailed description when read in conjunction with the drawings, in which:

[0028] Fig. 1 is a structural schematic diagram of a finger of a mechanical gripper in a closed state according to an exemplary embodiment of the present application.

[0029] Fig. 2 is a structural schematic diagram of a finger of a mechanical gripper in an open state according to an exemplary embodiment of the present application.

[0030] Fig. 3 is a three-dimensional structural schematic diagram of a mechanical gripper according to an exemplary embodiment of the present application.

[0031] Fig. 4 is a structural exploded schematic diagram of a mechanical gripper according to an exemplary embodiment of the present application.

[0032] Fig. 5 is a structural schematic diagram of a first support of a mechanical gripper according to an exemplary embodiment of the present application.

[0033] Fig. 6 is a partial structural schematic diagram of a mechanical gripper according to an exemplary embodiment of the present application.

[0034] Fig. 7 is a schematic view of a partial structure of the robot according to an exemplary embodiment of the present application.

[0035] Fig. 8 is a schematic view of a partial structure of a mechanical gripper according to an exemplary embodiment of the present application.

[0036] Figs. 9 and 10 are each a schematic view of a partial structure of a mechanical gripper according to an exemplary embodiment of the present application.

[0037] Fig. 11 is a schematic view of a second support member of a mechanical gripper according to an exemplary embodiment of the present application.

[0038] Fig. 12 is a schematic view of a partial structure of a mechanical gripper according to an exemplary embodiment of the present application.

[0039] Fig. 13 is a bottom view of a mechanical gripper according to an exemplary embodiment of the present application.

[0040] Fig. 14 is another schematic view of a mechanical gripper according to an exemplary embodiment of the present application.

[0041] Fig. 15 is a schematic view of a robot according to an exemplary embodiment of the present application. DETAILED DESCRIPTION

[0042] For a better understanding of the present application, various aspects of the present application will be described in greater detail below. It will be appreciated that these detailed descriptions are merely descriptive of exemplary embodiments of the present application and are not intended to limit the scope of the present application in any way. Throughout the specification, like reference numerals will refer to like elements every where the like reference numerals appear. The expression “and / or” includes any and all combinations of one or more of the associated listed items.

[0043] It should be noted that in the present specification, the expressions “first”, “second”, and so on are merely used to distinguish one feature from another feature, and do not represent any limitation on the features, especially do not represent any sequential order. Thus, without departing from the teachings of the present application, the first support member discussed in the present application can also be referred to as the second support member, and vice versa.

[0044] In the specification, the reference to “one embodiment”, “an embodiment”, “some embodiments”, and the like means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily referring to the same embodiment. Further, the particular features, structures, or characteristics can be implemented in both the described embodiment and in other embodiments without specific reference to the alternative embodiments.

[0045] In the drawings, the thicknesses of components, sizes, and the shapes of components have been slightly adjusted for ease of explanation. The drawings are merely examples and are not drawn to scale. For example, the sizes of the gripper assemblies depicted in the drawings in this application are not in proportion to one another. As used in this document, "substantially," "approximately," and like terms are used as terms of approximation and not as terms of degree, and are intended to account for the inherent deviations in a measuring or computing process.

[0046] It should be understood that expressions such as "comprise", "include", "have", "contain", and / or "comprising", "including", and / or "having" and the like, used in the present description, are intended to be open-ended terms that specifically do not exclude the presence of one or more other features, elements, components, and / or combinations of them. In addition, when expressions such as "at least one of" appear after a list of two or more items, that list is intended to be an open-ended list, specifically to mean that one or more of the items in the list can be present, and that the item or items that can be present can be only one of the items in the list, or can be more than one of the items in the list. Furthermore, when describing embodiments of the application, the use of "can" means "one or more embodiments of the application". Also, the use of the term "exemplary" is intended to mean an example or an illustration.

[0047] It should also be understood that the meanings of expressions such as "on", "over", and "above" should be interpreted in the broadest possible way, such that "on" means not only "directly on", but also includes the meaning of "on" with intermediate features or layers therebetween, and "over" or "above" means not only "over" or "above", but also can include the meaning of "over" or "above" with no intermediate features or layers therebetween (i.e., directly on).

[0048] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and not be interpreted in an overly formal or overly literal sense unless expressly so defined herein.

[0049] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict if necessary.

[0050] The features, principles, and other aspects of the present application will be described in detail below with reference to the accompanying drawings.

[0051] The mechanical gripper provided by the application can at least improve or solve the above problems. The mechanical gripper can be automatically locked in the case of sudden power failure, effectively preventing the load from sliding or falling; meanwhile, targeted sealing design is carried out, good waterproof and oil stain prevention performance is achieved; most of the torque formed by the load is transmitted to the shell by using a unique structure design, meeting the requirements of clamping force, eccentric load, volume and weight in complex scenes; in addition, real-time opening and closing amount and opening and closing speed of the mechanical gripper are controlled; the mechanical gripper has the advantages of small volume, light weight, low cost, simple operation and the like.

[0052] Fig. 1 is a structural schematic diagram of a finger of a mechanical gripper in a closed state according to an exemplary embodiment of the application. Fig. 2 is a structural schematic diagram of a finger of a mechanical gripper in an open state according to an exemplary embodiment of the application. As shown in Figs. 1 and 2, the mechanical gripper 100 includes a driving assembly 110, a gripper assembly 120 and a movable assembly 130. In some embodiments, the driving assembly 110 includes a driving rod 111 and a driver 112, and the driver 112 can drive the movement of the driving rod 111. The movable assembly 130 is coupled with the driving rod 111 and moves along the axial direction (for example, the z direction or the opposite direction of z) of the driving rod 111 under the driving of the driving rod 111. The gripper assembly 120 is connected with the movable assembly 130, and the gripper assembly 120 can include a plurality of fingers 121, and the movable assembly 120 drives the plurality of fingers 121 to move close to or away from each other to realize opening and closing during movement in the z direction or the opposite direction of z.

[0053] It can be understood that when the movable assembly 120 moves in the z direction, the distance between the plurality of fingers 121 decreases, thereby realizing the limiting and grabbing of the target object; when the movable assembly 120 moves in the opposite direction of z, the distance between the plurality of fingers 121 increases, thereby realizing the release of the grabbed object.

[0054] It should be noted that the number of fingers 121 in the drawings of the application is 2, which is only an exemplary illustration, and is not a limitation of the application. Those skilled in the art can set different numbers of fingers without departing from the application. For example, the number of fingers 121 is set to 3, 4, 5, 6 or even more.

[0055] In some embodiments, the fingers 121 include grooves 121a extending along the y direction. The grooves 121a will form a clamping space when the fingers 121 are close to each other. The inventors of the present application have found that the mechanical gripper 100 needs to bear a large eccentric load when picking up a target object, because the target object can have a long handle (e.g. a frying basket, a frying pan, etc.). This not only puts a requirement on the structural strength of the mechanical gripper 100 as a whole, but also challenges the clamping manner thereof. Too small clamping force of the fingers 121 and insufficient friction between the fingers 121 and the target handle can both cause a risk of falling of the target object. The design of the grooves 121a can provide support in the z direction to the target handle, and convert the key force from friction to support force, thereby effectively avoiding falling of the object during clamping.

[0056] For example, the clamping part of the fingers 121, i.e. the part in contact with the target object, includes a flexible piece 1211. The flexible piece 1211 can increase the friction when in contact with the target object, and also play a role of buffering protection during clamping. The flexible piece 1211 is, for example, a food-grade silica gel or the like.

[0057] In some embodiments, the driver 112 drives the driving rod 111 to rotate in the power-on state, and self-locks to limit the movement of the driving rod 111 in the power-off state. The driving rod 111 cooperates with the movable assembly 110, and drives the movable assembly 120 to move. When the driver 112 is powered off, the driver 112 forms a self-locking, and the rotation of the driving rod 111 is "locked", thereby ensuring that the movement of the movable assembly 110 immediately stops, and further ensuring that the fingers 121 will not open after power-off. The self-locking design can effectively avoid sliding and falling of the clamped object in the case of sudden power-off of the mechanical gripper 100 or system.

[0058] For example, the driving rod 111 includes a threaded rod, the movable assembly 120 includes a threaded sleeve, and the coupling between the driving rod 111 and the movable assembly 120 includes a threaded cooperation of the threaded rod and the threaded sleeve.

[0059] FIG. 3 is a perspective structural schematic view of a mechanical gripper according to an exemplary embodiment of the present application. As shown in FIG. 3, the mechanical gripper 100 further includes a housing 140. The housing 140 can be combined by a front housing 141, a rear housing 142 and an upper housing 143. The connection manner of the front housing 141, the rear housing 142 and the upper housing 143 includes at least one of bolt connection, adhesive bonding and welding. When bolt connection is adopted, a sealing washer can be additionally installed between the bolt and the housing 140 to ensure the sealing property of the overall structure.

[0060] Fig. 4 is an exploded view of the mechanical gripper according to an example embodiment of the present application. As shown in Figs. 1 and 4, the gripper assembly 120 further comprises a first connecting member 122, a transverse connecting member 124, and a first support member 125. Fig. 5 is a structural view of the first support member of the mechanical gripper according to an example embodiment of the present application. As shown in Figs. 4 and 5, the first support member 125 comprises a first support member first portion 1251 and a first support member second portion 1252. The radial (z direction / anti-z direction) dimension of the first support member first portion 1251 is greater than that of the first support member second portion 1252. One end of the first connecting member 122 is connected to the first support member second portion 1252, and the other end is connected to the finger 121 for driving the movement of the finger 121. One end of the transverse connecting member 124 is connected to the movable assembly 130, and the other end is connected to the first support member first portion 1251 for driving the rotation of the first support member 125.

[0061] In some embodiments, the connection between the first support member 125 and one end of the transverse connecting member 124 comprises a key connection, and the connection between the other end of the transverse connecting member 124 and the movable assembly 130 comprises a hinge connection. When the transverse connecting member 124 rotates around the hinge end, the end connected to the first support member 125 drives the rotation of the first connecting member 122. The first support member second portion 1252 can be designed at least partially as a flat surface, and the rotation of the flat surface drives the collective rotation of the end of the first connecting member 122, thereby driving the opening and closing of the finger 121.

[0062] For example, the first support member 125 penetrates the housing 140. Further, the first support member second portion 1252 is located on the side of the housing 140 away from the driving assembly 110, i.e., the outer side of the housing 140.

[0063] Fig. 6 is a partial structural view of the mechanical gripper according to an example embodiment of the present application. Fig. 7 is a partial structural view of the mechanical gripper based on Fig. 6 with the transverse connecting member removed. For the convenience of observing the connection relationship of the internal structure of the mechanical gripper 100, the transverse connecting member 124 in Fig. 6 is removed to form the view shown in Fig. 7. As shown in Figs. 3 to 7, the mechanical gripper 100 further comprises a first sealing member 150. The first sealing member 150 is located on the side of the housing 140 away from the driving assembly 110, i.e., the outer side of the housing 140, and is in contact with the gripper assembly 120 to form a seal.

[0064] In some embodiments, the first sealing member 150 is sleeved on the first support member 125, and is in mutual extrusion with the end of the first connecting member 122.

[0065] Figure 8 is a schematic diagram of a partial structure of a mechanical gripper according to an exemplary embodiment of the present application. As shown in Figure 8, the mechanical gripper 100 further comprises a sealing bearing 160, which can be mounted on the housing 140 and sleeved on the surface of the first portion 1251 of the first support 125. The first surface of the sealing bearing 160 (e.g., the surface on the side opposite to y) is in contact with the first seal 150. The sealing bearing 160 provides the supporting force of the first support 125, and the inner ring of the sealing bearing 160 rotates synchronously during the rotation of the first support 125.

[0066] Exemplarily, the outer surface of the sealing bearing 160 can be in interference fit with the housing 140, and can be bonded or welded to the fixed position of the housing 140 to form a seal therebetween. The sealing manner of the sealing bearing 160 comprises at least one of the non-contact rubber seal with skeleton on both surfaces and the contact rubber seal with skeleton on both surfaces.

[0067] In some embodiments, the first seal 150 is closely attached to the sealing bearing 160 and generates relative friction, which puts higher requirements on the material selection of the first seal 150. The first seal 150 needs to have good wear resistance, small roughness, sufficient resistance to plastic deformation, and even self-lubricating ability. Exemplarily, the material of the seal comprises at least one of graphite, carbon fiber, polytetrafluoroethylene, polyformaldehyde thermoplastic polymer, and semi-metallic material. The semi-metallic material can be a composite material formed by a metal and a non-metallic material, such as a material formed by mixing flexible graphite and a metal matrix, or a material made of a steel plate as a matrix, intermediate sintered spherical bronze powder, surface-rolled polytetrafluoroethylene, and a mixture.

[0068] The first seal 150 cooperates with the housing 140, the sealing bearing 160, the first connecting member 122, and the first support 125 to form a good sealing effect. When the mechanical gripper 100 is in contact with a liquid, since the first surface of the sealing bearing 160 and the first seal 150 both have small roughness, they are closely attached in actual work, and the outer surface of the sealing bearing 160 and the first support 125 can form, for example, interference fit, so that the liquid is not sufficient to penetrate the gap between the first surface of the sealing bearing 160 and the first seal 150 and the mating surface of the sealing bearing 160 and the first support 125 to enter the inside of the system under the action of its own surface tension. The above structural design can make the mechanical gripper 100 achieve IP55 level or even higher waterproof and oil-proof effect.

[0069] The inventor of the present application also found that when facing complex working conditions, the mechanical gripper 100 has the possibility of long-time contact with liquid (including partial or full immersion in liquid, or even bearing certain depth pressure), or persistent placement in a steam environment, which puts higher requirements on the sealing performance of the mechanical gripper 100. To solve the above technical problems, the present application also provides a sealing scheme as described below.

[0070] With continuous reference to FIG. 8, the mechanical gripper 100 further comprises a second seal 170. The second seal 170 can be located on the side of the sealing bearing 160 away from the first seal 150, and can be limited by the transverse connecting piece 124 and the first sealing bearing 160, and in contact with the second surface of the sealing bearing 160 and the first support 125 respectively to form axial (along the y direction) and radial direction seals respectively.

[0071] FIGS. 9 and 10 are partial structural schematic diagrams of a mechanical gripper according to an exemplary embodiment of the present application. For the convenience of observing the internal structure, part of the shell in FIG. 3 is removed to form the diagrams shown in FIGS. 4 and 5 respectively. As can be seen from FIGS. 3, 9 and 10, the space formed by the shell 140 includes a first space 140A and a second space 140B. The driver 112 can be located in the first space, and the movable assembly 130, the first support first part 1251 and the transverse connecting piece 124 are located in the second space 140B.

[0072] In some embodiments, the second space 140B is filled with a filler. The filler can be solid, semi-solid, gel, etc., and can be filled in part of the second space 140B, such as between the connecting surfaces and / or gaps of various connecting structures; or the second space 140B can be filled with the filler. The presence of the filler can lubricate the various connecting structures on the one hand, and contribute to the overall sealing on the other hand, for example, by selecting sealing grease or ordinary grease as the filler.

[0073] Exemplarily, the material of the second seal 170 can include flexible materials such as sealing silica gel, etc., and can also include the same material as the first seal 150. When the material of the second seal 170 is selected from at least one of graphite, carbon fiber, polytetrafluoroethylene, polyoxymethylene thermoplastic polymer and semi-metallic material, the second space 140B is filled with the filler.

[0074] In some embodiments, the housing 140 further comprises a limit block 145 extending into the second space 140B, i.e. the side of the driver 112 close to the movable assembly 130, for limiting the movement of the lateral connecting member 124 along the z direction. When the lateral connecting member 124 moves along the z direction, it will contact the limit block 145 at the limit position, thereby avoiding the collision and friction between the movable assembly 130 and the top of the second space 140B and the excessive compression between the plurality of fingers 121 due to the over-range of the stroke of the movable assembly 130.

[0075] For example, the movable assembly 130 can comprise a movable sleeve 131 and a hinged rod 132. The movable sleeve 131 is sleeved on the driving rod 111 and can move along the z direction or the reverse direction of the z direction under the rotation of the driving rod 111; one end of the hinged rod 132 is hingedly or fixedly connected with the movable sleeve 131, and the other end is hingedly connected with the lateral connecting member 124.

[0076] It can be understood that, if the limit block 145 is not provided, when the stroke of the movable assembly 130 is over-range, the hinged end of the hinged rod 132 and the lateral connecting member 124 will collide and rub with the top of the second space 140B, causing the excessive compression between the plurality of fingers 121 and affecting the structure of the gripper assembly 120, and even destroying the parallelogram structure maintained by the gripper assembly 120 during movement. In order to avoid the above collision and friction, it is necessary to lengthen the stroke of the movable assembly 130, i.e. lengthen the length of the driving rod 111, and further lengthen the length of the mechanical gripper 100 along the z direction. The present application introduces the design of the limit block 145, which can ensure that the above collision and friction do not occur and the excessive compression between the plurality of fingers 121 at the limit position (the position where the limit block 145 contacts the lateral connecting member 124). The presence of the limit block 145 is beneficial to reduce the length of the mechanical gripper 100 in the z direction, thereby reducing the length of the mechanical gripper 100.

[0077] For example, the surface of the limit block 145 facing the lateral connecting member 124 is parallel to the surface of the lateral connecting member 124 facing the limit block 145, thereby effectively reducing the impact transmitted to the gripper assembly 120 and the movable assembly 130 under the premise of meeting the limiting requirement. The clamping force when the plurality of fingers 121 reach the closed state can be adjusted by adjusting the length of the limit block 145 in the z direction.

[0078] Figure 11 is a schematic diagram of a structure of a second support member of the mechanical gripper according to an exemplary embodiment of the present application. As shown in Figures 4 and 11, the gripper assembly 120 further comprises a second support member 126 and a second connecting member 123. The second support member 126 comprises a second support member first portion 1261 and a second support member second portion 1262, and the second support member second portion 1262 is located at a side of the housing 140 away from the driving assembly 110. The first seal 150 is sleeved on the second support member 126. Similar to the first support member 125, the end of the second connecting member 123 near the side of the housing 140 is in contact with the first seal 150.

[0079] In some embodiments, the second support member 126 can also be used in cooperation with the seal bearing 160, and the second seal 170 can be located at a side of the seal bearing 160 away from the first seal 150 and in contact with the second surface of the seal bearing 160 and the second support member 126 respectively to form a seal.

[0080] In some embodiments, one end of the second connecting member 123 is connected to the second support member second portion 1262, and the other end is connected to the fingers 121. For example, during the process of the fingers 121 moving towards or away from each other, the first connecting member 122 and the second connecting member 123 remain parallel to each other so that the angle of the fingers 121 relative to the axis (z direction) does not change. The lengths of the first connecting member 122 and the second connecting member 123 can be the same. In other words, the second connecting member 123 and the first connecting member 122 form two parallel sides of a parallelogram, which is beneficial for the fingers 121 to move along the x direction during the opening and closing process, and can achieve the parallel clamping of the objects by the fingers 121, thereby ensuring the stability during the gripping and releasing of the objects such as long strip-shaped objects. Especially for long strip-shaped objects with circular, elliptical, square, and other regular or irregular polygonal cross sections, if the fingers 121 move along a direction other than the x direction to form a clamping (for example, the lower end of the fingers 121 contacts first to form an inverted triangular clamping mode when the fingers 121 are closed), the clamping area between the fingers 121 and the target object will be reduced, which can easily cause the clamping to be not firm and cause shaking.

[0081] Figure 12 is a schematic diagram of a partial structure of the mechanical gripper according to an exemplary embodiment of the present application. For the convenience of observing the internal structure, half of the housing 140 has been removed for display. As shown in Figure 12, the first connecting member 122 comprises a first connecting rod 1221, a second connecting rod 1222, and a web plate 1223. The first connecting rod 1221 is located at one side of the housing 140, and the second connecting rod 1222 is oppositely arranged with the first connecting rod 1221 and located at the other side of the housing 140. One end of the web plate 1223 is connected to the first connecting rod 1221, and the other end is connected to the second connecting rod 1222.

[0082] The inventor of the present application also found that in a kitchen scenario, for example, some kitchen utensils usually need to be in contact with a heat source, and therefore are usually provided with a long handle for heat dissipation or to avoid scalding. The center of gravity of such kitchen utensils will be concentrated on the body, especially after containing things, thereby forming a large eccentric load. For example, the wok during the cooking process forms an eccentric load on the human hand, and the human hand needs to overcome the gravity of the wok while also overcoming a large torque and bending moment. In the field of robotics, similar problems also exist, which requires the mechanical gripper 100 to not only have the ability to bear a large central load but also to overcome a large eccentric load.

[0083] With continued reference to FIG. 12, when facing a large eccentric load, the first connecting member 122 will bear the torque formed by the eccentric load and the gravity of the load. The first connecting member 122 of the present application can transmit the torque to the sealed bearing 160 through the first support member 125. Since the sealed bearing 160 is fixed on the housing 140, the housing 140 ultimately bears most of the torque formed by the eccentric load. This design is beneficial to reduce the rigidity requirement of the first connecting member 122, and can reduce the use of materials while meeting the load gravity. The connection mode of the first connecting rod 1221, the second connecting rod 1222, and the rib plate 1223 is formed, thereby further reducing the weight of the mechanical gripper 100.

[0084] For example, the material of the housing 140 includes at least one of metal aluminum, aluminum alloy, stainless steel, metal titanium, and carbon fiber; the materials of the first connecting rod 1221, the second connecting rod 1222, and the rib plate 1223 all include at least one of stainless steel and metal titanium.

[0085] In some embodiments, the various materials described above can further meet the application requirements in a kitchen scenario.

[0086] With continued reference to FIG. 2, the mechanical gripper can also include a sensor 180, a signal acquisition unit (not shown), and a control unit (not shown). The sensor 180 can be located in the second space 140B; the signal acquisition unit and the control unit are both located in the first space 140A. The signal acquisition unit is used to record the rotation information of the driving rod 111, and the control unit controls the real-time opening and closing amount of the plurality of fingers 121 based on the rotation information. The sensor 180 is used to feed back the signal of the movement of the movable assembly 130 to the zero position and the target position to the control unit, and the control unit controls the maximum opening and closing amount of the plurality of fingers 121 through motion planning. When the movable assembly 130 moves to the target position, the fingers 121 reach the maximum opening and closing amount.

[0087] For example, the number of sensors 180 can be multiple, some of which are used to record whether the movable assembly 130 moves to the zero position, which can be the preset initial position, and some of which are used to record the target position, i.e., the maximum stroke position of the movable assembly 130. The control unit stops the movable assembly 130 at the maximum stroke position through motion planning.

[0088] In some embodiments, the control unit controls the opening and closing speed of the mechanical gripper 100 through FOC (Field-Oriented Control). It can adopt at least one of the current control mode, the speed control mode and the position control mode. The signal acquisition unit, for example, is an encoder, which can record the rotation angle of the driver 112, and plan the stroke amount of the movable assembly 130 through the control unit, and then plan the real-time opening and closing amount of the fingers 121. For example, under the premise that the overall width (along the x direction) of the mechanical gripper 100 does not exceed 160 cm and the overall length (along the z direction) does not exceed 180 cm, the maximum opening and closing amount of the plurality of fingers 121 is not less than 100 mm. It can be understood that when facing different actual needs, the mechanical gripper 100 and each structural component cooperating therewith can be proportionally reduced or enlarged, so that the fingers 121 can achieve a smaller or larger maximum opening and closing amount.

[0089] In some embodiments, during the process of clamping the target object, the reaction force of the clamping force will be converted into the damping force of the driver 112, and the control unit can control the size of the clamping force through the size of the damping force feedback by the driver 112, so as to ensure that the target object can obtain a suitable clamping force.

[0090] FIG. 13 is a bottom view of the mechanical gripper according to an exemplary embodiment of the present application. As shown in FIG. 13, the mechanical gripper 100 further comprises an alignment bearing 113, which is installed at the bottom of the housing 140 and is sealed by a sealing cover. The side of the driving rod 111 in the reverse direction of z is coupled to the inner ring of the alignment bearing 113. The alignment bearing 113 can ensure the stability of the driving rod 111 during rotation, avoiding its shaking and eccentric rotation.

[0091] FIG. 14 is another structural schematic view of the mechanical gripper according to an exemplary embodiment of the present application. As shown in FIG. 14, the mechanical gripper 100 can further comprise an adapter 190. In some embodiments, the adapter 190 can be located only on the upper housing 143, or only on the outside of the front housing 141. In other embodiments, the number of adapters 190 includes multiple, and are respectively located on the upper housing 143 and the outside of the front housing 141.

[0092] In some embodiments, the interface portion of the housing 140 (including the joint of the front housing 141, the rear housing 142, and the upper housing 143) is provided with a flexible seal. For example, a groove can be formed along the entire inner edge of the front housing 141, the rear housing 142, and the upper housing 143, respectively, and the groove is filled with sealant and / or flexible rubber. When the front housing 141, the rear housing 142, and the upper housing 143 are aligned and coupled to each other, the sealant or flexible rubber will be squeezed to form a good sealing effect.

[0093] Another aspect of the present application also provides a robot. FIG. 15 is a structural schematic diagram of a robot according to an exemplary embodiment of the present application. As shown in FIG. 15, the robot 900 includes a mechanical gripper 100, a mechanical arm 200, and a controller (not shown). The controller is communicatively connected to the mechanical arm 200 and the mechanical gripper 100, and controls the movement of the mechanical arm 200 and the opening and closing of the plurality of fingers 121 by sending instructions, respectively. The end of the mechanical arm 200 is connected to the mechanical gripper 100, so as to drive the movement of the mechanical gripper 100 during the movement of the mechanical arm 200.

[0094] For example, the end of the mechanical arm 200 can be connected to the adapter 190 by bolts or screws. The adapter 190 can be arranged parallel to the z direction or perpendicular to the z direction, so that after being connected to the mechanical arm 200, the mechanical gripper 100 extends along the z direction or perpendicular to the z direction.

[0095] The robot 900 can be applied to many scenes such as finance, medical treatment, home, retail, security, education, etc. For example, the robot 900 can be used for cooking and cooking in a kitchen scene to automatically prepare food.

[0096] In some embodiments, the robot 900 can be used to hold kitchen utensils, which realizes the grasping of target utensils by regulating the movement and action of the mechanical arm 200 and the mechanical gripper 100. The robot 900 can hold both the central load with the center of gravity in the body of the utensil such as a condiment bottle and a bowl, and the eccentric load with the center of gravity outside the body such as a frying basket and a frying pan with a handle. The unique structural design described above transmits most of the torque generated by the load to the housing 140, has the ability to resist larger eccentric torque and bending moment, meets the requirements of eccentric load, clamping force in complex scenes, and realizes the requirements of volume and light weight.

[0097] In some embodiments, when the robot 900 suddenly loses power, the driver 112 interacts with other mechanical structures in the mechanical gripper 100, so that the plurality of fingers 121 can maintain the state at the time of power failure after power failure, realize self-locking, ensure the clamping of the clamped object, and effectively avoid the sliding and falling of the load (such as a frying basket) caused by sudden power failure during work.

[0098] It should be noted that the robot 900 relies on its structure and sealing design to achieve good waterproof and oil-proof performance for the part in close contact with oil fume. In addition, the robot 900 also achieves control of the real-time opening and closing amount and the opening and closing speed of the mechanical gripper 100, and has the advantages of low cost and simple operation.

[0099] Since the content and structure described above in relation to the mechanical gripper 100 can be completely or partially applicable to the robot 900 described herein, the related or similar content will not be described again.

[0100] The above description is only an embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the protection scope of the present application is not limited to the technical solutions formed by the specific combinations of the technical features described above, and should also cover other technical solutions formed by any combination of the technical features described above or their equivalent features without departing from the technical concept. For example, the technical solutions formed by mutual replacement of the above-described features and the technical features disclosed in the present application (but not limited to) having similar functions.

[0101] List of reference signs 100 mechanical gripper 110 movable assembly 111 driving rod 112 driver 113 alignment bearing 120 gripper assembly 121 finger 121a recess 1211 flexible member 122 first connecting member 1221 first connecting rod 1222 second connecting rod 1223 rib plate 123 second connecting member 124 transverse connecting member 125 first support member 1251 first support member first part 1252 first support member second part 126 second support member 1261 second support member first part 1262 second support member second part 130 movable assembly 131 movable shaft sleeve 132 articulated rod 140 housing 140A first space 140B second space 141 front housing 142 rear housing 143 upper housing 150 first sealing member 160 sealing bearing 170 second sealing member 180 sensor 190 adapter 200 mechanical arm 900 robot

Claims

1. A mechanical gripper, characterized in that: include: a drive assembly including a drive rod; A movable assembly is coupled to the driving rod and moves along the axis of the driving rod under the drive of the driving rod; as well as The gripper assembly is connected to the movable assembly and includes a plurality of fingers. The movable assembly drives the plurality of fingers to move closer to or away from each other during movement along the axis.

2. The mechanical gripper according to claim 1, characterized in that: Also includes: a housing, covering the outer sides of the driving assembly and the movable assembly; as well as The first sealing member is located on a side of the housing away from the driving assembly and contacts the gripper assembly to form a seal.

3. The mechanical gripper according to claim 2, characterized in that: The gripper assembly further comprises: The first support member passes through the shell and includes a first support member first part and a first support member second part. The radial dimension of the first support member first part is greater than the radial dimension of the first support member second part, and the first support member second part is located on the side of the shell away from the drive assembly. The first sealing member is sleeved on the first support member.

4. The mechanical gripper according to claim 3, characterized in that: The gripper assembly further comprises: a first connecting member, one end of which is connected to the second portion of the first supporting member, and the other end of which is connected to the finger, for driving the movement of the finger; and A transverse connecting member, one end of which is connected to the movable assembly and the other end of which is connected to the first portion of the first supporting member, for driving the rotation of the first supporting member. The first supporting member drives the end of the first connecting member to rotate together. An end portion of the first connecting member contacts the first sealing member.

5. The mechanical gripper according to claim 4, characterized in that: The gripper assembly further comprises: a second support member, passing through the housing and comprising a second support member first portion and a second support member second portion, wherein the second support member second portion is located on a side of the housing away from the drive assembly, and the first sealing member is sleeved on the second support member; A second connecting member, one end of which is connected to the second portion of the second supporting member, and the other end of which is connected to the finger. In the process of the multiple fingers approaching or moving away from each other, the first connecting member and the second connecting member remain parallel to each other so that the angles of the multiple fingers relative to the axis remain unchanged, and the end of the second connecting member contacts the first sealing member.

6. The mechanical gripper according to claim 4, characterized in that: Also includes: a signal acquisition unit, configured to record the rotation information of the driving rod; as well as The control unit performs motion planning based on the rotation information of the driving rod to control the real-time opening and closing amounts of the plurality of fingers.

7. The mechanical gripper according to claim 6, characterized in that: Also includes: The sensor is used to feed back signals indicating that the movable component moves to a zero position and a target position to the control unit so as to control the maximum opening and closing amount of the plurality of fingers, wherein the target position corresponds to the maximum opening and closing amount of the plurality of fingers.

8. The mechanical gripper according to claim 7, characterized in that: The driving assembly includes a driver, and the housing includes a limit block, The limit block is located on a side of the driver close to the movable component and is used to limit the movement of the transverse connecting member along the axis direction. Wherein, the driver drives the driving rod to rotate when power is on to drive the movable assembly to move along the axis direction, and locks the rotation of the driving rod to limit the movement of the movable assembly when power is off.

9. The mechanical gripper according to claim 4, characterized in that: The first connecting member includes: a first connecting rod, located on one side of the housing; a second connecting rod, disposed opposite to the first connecting rod and located on the other side of the housing; and A rib plate has one end connected to the first connecting rod and the other end connected to the second connecting rod.

10. The mechanical gripper according to claim 3, characterized in that: The fingers include grooves, and when the fingers approach each other, the plurality of grooves form a clamping space, wherein the grooves extend along an axial direction parallel to the first support member.

11. The mechanical gripper according to claim 4, characterized in that: Also includes: A sealed bearing is mounted on the housing and sleeved on the surface of the first portion of the first support member, wherein the first surface of the sealed bearing contacts the first sealing member.

12. The mechanical gripper according to claim 11, characterized in that: Also includes: The second sealing member is located on a side of the sealed bearing away from the first sealing member and is in contact with the second surface of the sealed bearing and the first supporting member respectively.

13. The mechanical gripper according to claim 8, characterized in that: The housing has a first space and a second space, the driver and the control unit are located in the first space, the movable assembly, the first portion of the first support member and the transverse connection member are located in the second space, and the second space is filled with filler.

14. The mechanical gripper according to claim 9, characterized in that: The material of the shell includes at least one of metal aluminum, aluminum alloy, stainless steel, metal titanium and carbon fiber, the material of the first seal includes at least one of graphite, carbon fiber, polytetrafluoroethylene, polyoxymethylene thermoplastic polymer and semi-metallic material, and the material of the first connecting rod includes at least one of stainless steel and metal titanium.

15. A robot, characterized in that: include: The mechanical gripper according to any one of claims 1 to 14; robotic arm; as well as a controller, in communication with the robotic arm and the robotic gripper, for sending instructions to control the movement of the robotic arm and the opening and closing of the plurality of fingers; Wherein, the mechanical arm drives the mechanical gripper to move.

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