Gripping mechanism and method of gripping

Abstract

The application relates to a grabbing mechanism and a grabbing method thereof, which comprises a floating locking unit and a grabbing unit. The floating locking unit comprises a first support piece, an X-axis motion pair, a Y-axis motion pair, a second support piece, a locking driving piece and a locking shaft. The second support piece has a freedom degree of movement in a plane. The second support piece is provided with a locking hole. The locking driving piece drives the locking shaft to move along the Z-axis direction. The locking shaft passes through the locking hole and comprises a locking part, a releasing part and a transition part. The shaft diameter of the locking part is the same as the hole diameter of the locking hole. The shaft diameter of the releasing part is smaller than the hole diameter of the locking hole. The grabbing unit grabs products. When the products are grabbed, the grabbing mechanism is in a locking state, and the products can be accurately grabbed. When the products are assembled or placed, the grabbing mechanism is in a floating state, and the products can be assembled to another product with a certain tolerance or transferred to a carrier with a certain tolerance. The state switching of the grabbing mechanism is realized through a simple structure.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of article transfer, in particular to a grabbing mechanism and a grabbing method thereof. BACKGROUND

[0002] With the development of automation technology, robot automatic assembly method has been more and more widely applied. The robot grabs a product and then assembles it to another product. Since there is a certain tolerance between the product and the other product, the product may not be accurately assembled to the other product during assembly.

[0003] A robot gripper three-degree-of-freedom floating device is disclosed in Chinese patent application CN112976039A, which comprises a robot mounting plate, a vertical floating frame, a horizontal floating plate, a vertical locking mechanism and a horizontal locking mechanism. The vertical floating frame is connected to the robot mounting plate in a vertically movable manner. The horizontal floating plate is arranged in the vertical floating frame in a horizontally movable manner. The vertical floating frame is provided with a gripper mounting plate outside the side away from the robot mounting plate. The horizontal floating plate is provided with a central shaft, and the central shaft is fixedly connected to the gripper mounting plate after passing through the vertical floating frame. A gap is arranged between the central shaft and the vertical floating frame. The vertical floating frame is locked by the vertical locking mechanism, and the horizontal floating plate is locked by the horizontal locking mechanism. The above-mentioned robot gripper three-degree-of-freedom floating device is relatively easy to switch from the locked state to the floating state, but cannot return to the locked state from the floating state without stopping. How to switch the locking state and the floating state at any time during use is a technical problem to be solved in the field. SUMMARY

[0004] To this end, the present application provides a grabbing mechanism and a grabbing method thereof, which can switch the locking state and the floating state at any time during use.

[0005] To solve the above technical problems, the present application provides a grabbing mechanism, which comprises:

[0006] The floating locking unit comprises a first support member, an X-axis movement pair, a Y-axis movement pair, a second support member, a locking driving member and a locking shaft. The second support member is connected to the first support member through the X-axis movement pair and the Y-axis movement pair. The second support member has a freedom of movement in a plane relative to the first support member. The second support member is provided with a locking hole. The locking driving member is connected to the first support member and drives the locking shaft to move along the Z-axis direction. The locking shaft extends along the Z-axis direction and passes through the locking hole. The locking shaft comprises a locking portion, a release portion and a transition portion at different positions along the Z-axis direction. The shaft diameter of the locking portion is the same as the hole diameter of the locking hole. The shaft diameter of the release portion is smaller than the hole diameter of the locking hole. The transition portion smoothly connects the locking portion and the release portion.

[0007] The grabbing unit is connected to the second support member and grabs products.

[0008] Further, the locking portion and the release portion are both cylindrical, and the transition portion is in the shape of a circular truncated cone.

[0009] Further, the floating locking unit further comprises a Z-axis guide member connected to the first support member. The Z-axis guide member is provided with a guide hole through which the locking shaft passes. The guide hole guides the movement of the locking shaft along the Z-axis direction.

[0010] Further, the guide hole is connected to the locking portion.

[0011] Further, the locking shaft comprises two locking portions, one release portion and two transition portions. The two ends of the release portion are connected to the two locking portions through the two transition portions respectively. The Z-axis guide member comprises two guide portions located on the two sides of the second support member along the Z-axis direction. The two guide portions are both provided with the guide hole, and the two guide holes are connected to the two locking portions respectively.

[0012] Further, the Z-axis guide member further comprises a connecting portion connected between the two guide portions. The connecting portion is fixed relative to the first support member.

[0013] Further, the X-axis movement pair comprises an X-axis sliding rail and an X-axis sliding block. The X-axis sliding rail is fixed relative to the first support member. The X-axis sliding block is slidingly connected to the X-axis sliding rail along the X-axis direction.

[0014] The Y-axis movement pair comprises a Y-axis guide rail and a Y-axis sliding block. The Y-axis guide rail is fixed relative to the X-axis sliding block. The Y-axis sliding block is slidingly connected to the Y-axis guide rail along the Y-axis direction. The second support member is fixed relative to the Y-axis sliding block.

[0015] Further, the floating locking unit comprises two X-axis movement pairs, two Y-axis movement pairs and two second bracket members, each X-axis movement pair comprises one X-axis sliding rail and two X-axis sliding blocks, each Y-axis sliding rail is fixed opposite to the two X-axis sliding blocks on different X-axis sliding rails, and the two second bracket members are fixed opposite to the Y-axis sliding blocks of the two Y-axis movement pairs, respectively.

[0016] The grabbing mechanism comprises two grabbing units, and the two grabbing units are connected to the two second bracket members, respectively.

[0017] Further, the grabbing unit comprises a clamping driving member and two clamping jaws, the clamping driving member is connected to the second bracket member and drives the two clamping jaws to open and close along the Y-axis direction.

[0018] Further, the grabbing method of the grabbing mechanism, when the grabbing mechanism grabs the product, the locking part is connected with the locking hole, and when the grabbing mechanism releases the product, the releasing part is connected with the locking hole.

[0019] The above technical solutions of the present application have the following advantages compared with the prior art:

[0020] 1) The grabbing mechanism and the grabbing method thereof can switch the locking state and the floating state of the grabbing mechanism at any time by setting the floating locking unit, the grabbing mechanism is in the locking state when grabbing the product, the product can be accurately grabbed, the grabbing mechanism is in the floating state when assembling or releasing the product, the product can be assembled to another product with a certain tolerance or transferred to a carrier with a certain tolerance, and the state switching of the grabbing mechanism is realized by a simple structure.

[0021] 2) The locking part and the releasing part of the grabbing mechanism and the grabbing method thereof are cylindrical, the transition part is frustoconical, the locking shaft is regular in shape and high in size accuracy, easy to manufacture and process, and good in mechanical properties.

[0022] 3) The grabbing mechanism and the grabbing method thereof set the Z-axis guide member, so that the position accuracy of the locking shaft is high.

[0023] 4) The grabbing mechanism and the grabbing method thereof, a small part of the locking shaft is the releasing part, only needs to cooperate with the locking hole, the main part of the locking shaft is the locking part, the locking part cooperates with the locking hole and the guide hole, the diameter of the locking part is large, and the overall strength of the locking shaft is high.

[0024] 5) The grabbing mechanism and the grabbing method thereof, the locking shaft comprises two locking sections, one releasing section and two transition sections, and the Z-axis guide piece comprises two guide sections, which are matched with the two locking sections, on the one hand, the strength of the locking shaft is further improved, and on the other hand, two points determine a straight line, and the movement track of the locking shaft is more accurate;

[0025] 6) The grabbing mechanism and the grabbing method thereof, the Z-axis guide piece further comprises a connecting section, the Z-axis guide piece is connected as a whole, and the installation of the Z-axis guide piece is facilitated;

[0026] 7) The grabbing mechanism and the grabbing method thereof, the X-axis movement pair and the Y-axis movement pair are both movement pairs, and the two movement pairs are matched with each other to realize the floating of the second support piece in the plane;

[0027] 8) The grabbing mechanism and the grabbing method thereof, the grabbing mechanism comprises two X-axis movement pairs, two Y-axis movement pairs, two second support pieces and two grabbing units, and the grabbing mechanism can more stably grab the articles;

[0028] 9) The grabbing mechanism and the grabbing method thereof, the grabbing unit is a clamping jaw, and the grabbing unit can realize the grabbing, installation and transfer of the product. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to make the content of the application more easily understood, the application will be further described in detail below according to the specific embodiments of the application and in combination with the drawings.

[0030] Figure 1 It is a schematic view of the grabbing mechanism in the application from one angle;

[0031] Figure 2 It is a schematic view of the floating locking unit in the application;

[0032] Figure 3 It is a schematic view of the second support piece in the application;

[0033] Figure 4 It is a schematic view of the locking shaft in the application;

[0034] Figure 5 It is a schematic view of the Y-axis guide piece in the application.

[0035] Description of the drawings: 1, floating locking unit; 11, first support piece; 12, X-axis kinematic pair; 121, X-axis slide rail; 122, X-axis slide block; 13, Y-axis kinematic pair; 131, Y-axis guide rail; 132, Y-axis slide block; 14, second support piece; 141, locking hole; 15, locking drive piece; 16, locking shaft; 161, locking part; 162, release part; 163, transition part; 17, Z-axis guide piece; 171, guide hole; 172, guide part; 173, connecting part;

[0036] 2, grabbing unit; 21, clamping drive piece; 22, clamping jaw. DETAILED DESCRIPTION

[0037] The present application will be further described below in conjunction with the drawings and specific embodiments, so that those skilled in the art can better understand the present application and implement it, but the embodiments are not limiting the present application. Example one

[0038] Reference Figures 1 to 5 An embodiment of the grabbing mechanism provided by the present application is shown.

[0039] The grabbing mechanism comprises:

[0040] The floating locking unit 1 comprises a first support piece 11, an X-axis kinematic pair 12, a Y-axis kinematic pair 13, a second support piece 14, a locking drive piece 15 and a locking shaft 16. The second support piece 14 is connected to the first support piece 11 through the X-axis kinematic pair 12 and the Y-axis kinematic pair 13. The second support piece 14 has the freedom of movement in the plane relative to the first support piece 11. The second support piece 14 is provided with a locking hole 141. The locking drive piece 15 is connected to the first support piece 11 and drives the locking shaft 16 to move along the Z-axis direction. The locking shaft 16 extends along the Z-axis direction and passes through the locking hole 141. The locking shaft 16 comprises a locking part 161, a release part 162 and a transition part 163 located at different positions along the Z-axis direction. The shaft diameter of the locking part 161 is the same as the hole diameter of the locking hole 141. The shaft diameter of the release part 162 is smaller than the hole diameter of the locking hole 141. The transition part 163 smoothly connects the locking part 161 and the release part 162.

[0041] The grabbing unit 2 is connected to the second support piece 14 and grabs the product.

[0042] When the locking shaft 16 is axially moved by the locking driving member 15, when the locking part 161 of the locking shaft 16 is matched with the locking hole 141, the locking shaft 16 is tightly matched with the locking hole 141, thus the second support member 14 cannot move along the X-axis direction and the Y-axis direction relative to the locking shaft 16, the position of the second support member 14 is fixed, thus the position of the grabbing unit 2 is also fixed, at this time, the grabbing mechanism is in the locking state, and the product can be accurately grabbed; when the releasing part 162 of the locking shaft 16 is matched with the locking hole 141, there is a gap between the locking shaft 16 and the locking hole 141, thus the second support member 14 has the freedom of moving a small distance along the X-axis direction and the Y-axis direction relative to the locking shaft 16, thus the position of the grabbing unit 2 can be slightly floated, at this time, the grabbing mechanism is in the floating state, and the grabbing mechanism can float the product to another product with a certain tolerance or float the product to a carrier with a certain tolerance. The different parts of the outer side surface of the locking shaft 16 should be smoothly connected without obvious steps or mutations, so that the locking shaft 16 can smoothly pass through the locking hole 141 at different positions when it is axially moved.

[0043] By arranging the floating locking unit 1, the locking state and the floating state of the grabbing mechanism can be switched at any time, when the product is grabbed, the grabbing mechanism is in the locking state, and the product can be accurately grabbed, when the product is assembled or transferred, the grabbing mechanism is in the floating state, and the product can be floated to another product with a certain tolerance or floated to a carrier with a certain tolerance, and the state switching of the grabbing mechanism is realized by a simple structure.

[0044] The first support member 11 is used for external connection and serves as the mounting base of the floating locking unit 1, and in the embodiment, the first support member 11 is a support plate. The X-axis movement pair 12 and the Y-axis movement pair 13 are used for translating the grabbing unit 2 in an accurate plane, and the specific structure of the X-axis movement pair 12 and the Y-axis movement pair 13 will be described below. The second support member 14 serves as the mounting base of the grabbing unit 2, and in the embodiment, the second support member 14 is a support plate. The grabbing unit 2 can grab the product and then assemble or transfer the product, and the specific structure of the grabbing unit will be described below.

[0045] In the embodiment, the locking part 161 and the releasing part 162 are both cylindrical, and the transition part 163 is a circular truncated cone.

[0046] The locking part 161 and the releasing part 162 are both cylindrical, and the transition part 163 is a circular truncated cone, and both the cylinder and the circular truncated cone are revolution bodies, on the one hand, the locking shaft 16 smoothly transitions in the circumferential direction and the axial direction, and the locking shaft 16 is not easy to jam with the locking hole 141, on the other hand, the cylinder and the circular truncated cone are mature in processing technology, the processing precision of the locking shaft 16 can be improved, and the mechanical properties of the locking shaft 16 are good.

[0047] In this embodiment, the floating locking unit 1 further includes a Z-axis guide 17, which is connected to the first support member 11. The Z-axis guide 17 is provided with a guide hole 171, through which the locking shaft 16 passes. The guide hole 171 guides the locking shaft 16 to move along the Z-axis direction.

[0048] When the aforementioned gripping mechanism is in the locked state, it precisely grips the product. Therefore, the positional accuracy of the gripping unit 2 is relatively high. The positional accuracy of the gripping unit 2 depends on the positional accuracy of the second support member 14, which in turn depends on the positional and shape accuracy of the locking shaft 16. Therefore, the dimensional and positional accuracy of the locking shaft 16 itself is required to be high, especially the positional and shape accuracy of the locking portion 161 of the locking shaft 16. By providing the Z-axis guide 17, the movement of the locking shaft 16 can be guided, ensuring the positional accuracy of the locking shaft 16. The Z-axis guide 17 ensures a high level of positional accuracy for the locking shaft 16.

[0049] In this embodiment, the guide hole 171 is connected to the locking part 161.

[0050] When the gripping mechanism is in the locked state, the guide hole 171 contacts the locking part 161. When the gripping mechanism is in the released state, the guide hole 171 contacts the locking part 161. A small part of the locking shaft 16 is the release part 162, which only needs to cooperate with the locking hole 141. The main part of the locking shaft 16 is the locking part 161, which cooperates with the locking hole 141 and the guide hole 171. The locking part 161 has a large diameter, and the overall strength of the locking shaft 16 is high.

[0051] In this embodiment, the locking shaft 16 includes two locking portions 161, one release portion 162, and two transition portions 163. The two ends of the release portion 162 are connected to the two locking portions 161 through the two transition portions 163. The Z-axis guide 17 includes two guide portions 172, which are located on both sides of the second support member 14 along the Z-axis. Each guide portion 172 is provided with a guide hole 171, which is connected to the two locking portions 161.

[0052] The shaft diameter of the locking portion 161 is the same as the large end diameter of the transition portion 163, the locking portion 161 and the large end of the transition portion 163 are connected to each other, the shaft diameter of the releasing portion 162 is the same as the small end diameter of the transition portion 163, and the releasing portion 162 and the small end of the transition portion 163 are connected to each other. The locking shaft 16 includes two locking portions 161, one releasing portion 162, and two transition portions 163, and the Z-axis guide 17 includes two guide portions 172, which are matched with the two locking portions 161. On the one hand, the strength of the locking shaft 16 is further improved, and on the other hand, two points determine a straight line, and the movement trajectory of the locking shaft 16 is more accurate.

[0053] In the embodiment, the Z-axis guide 17 further includes a connecting portion 173, which is connected between the two guide portions 172, and the connecting portion 173 is fixed relative to the first support 11.

[0054] In the embodiment, the Z-axis guide 17 is substantially in the shape of a concave character, the groove bottom of the concave character is the connecting portion 173, the groove wall of the concave character is the guide portion 172, and the guide hole 171 penetrates the inner side surface and the outer side surface of the groove wall. The connecting portion 173 connects the Z-axis guide 17 as a whole, which facilitates the connection of the Z-axis guide 17 and the first support 11.

[0055] In the embodiment, the X-axis movement pair 12 includes an X-axis sliding rail 121 and an X-axis sliding block 122, the X-axis sliding rail 121 is fixed relative to the first support 11, and the X-axis sliding block 122 is slidingly connected to the X-axis sliding rail 121 in the X-axis direction.

[0056] The Y-axis movement pair 13 includes a Y-axis guide rail 131 and a Y-axis sliding block 132, the Y-axis guide rail 131 is fixed relative to the X-axis sliding block 122, the Y-axis sliding block 132 is slidingly connected to the Y-axis guide rail 131 in the Y-axis direction, and the second support 14 is fixed relative to the Y-axis sliding block 132.

[0057] The X-axis sliding rail 121 and the X-axis sliding block 122 constitute an X-axis movement pair, and the Y-axis guide rail 131 and the Y-axis sliding block 132 constitute a Y-axis movement pair. The X-axis movement pair 12 and the Y-axis movement pair 13 are both movement pairs, and the two movement pairs cooperate with each other to realize the smooth floating of the second support 14 in the plane.

[0058] In the embodiment, the floating locking unit 1 includes two X-axis movement pairs 12, two Y-axis movement pairs 13, and two second support members 14. Each X-axis movement pair 12 includes one X-axis sliding rail 121 and two X-axis sliding blocks 122. Each Y-axis sliding rail 131 is fixed opposite to the two X-axis sliding blocks 122 on different X-axis sliding rails 121. The two second support members 14 are fixed opposite to the Y-axis sliding blocks 132 of the two Y-axis movement pairs 13, respectively.

[0059] The grabbing mechanism includes two grabbing units 2 connected to the two second support members 14, respectively.

[0060] In the embodiment, the first support member 11, the X-axis movement pair 12, the Y-axis movement pair 13, and the second support member 14 are connected in sequence. The X-axis movement pair 12 needs to bear a large weight, so two X-axis movement pairs 12 are arranged. The Y-axis movement pair 13, the second support member 14, and the grabbing unit 2 are all arranged as two, so that the two grabbing units 2 grab two positions of the product, and the grabbing mechanism is more stable when grabbing the product. The grabbing mechanism includes two X-axis movement pairs 12, two Y-axis movement pairs 13, two second support members 14, and two grabbing units 2, which can more stably grab the product.

[0061] In the embodiment, the grabbing unit 2 includes a clamping driving member 21 and two clamping jaws 22. The clamping driving member 21 is connected to the second support member 14 and drives the two clamping jaws 22 to open and close along the Y-axis direction.

[0062] The opening and closing movement of the two clamping jaws 22 means that the two clamping jaws 22 move close to each other along the Y-axis direction and move away from each other along the Y-axis direction. When the two clamping jaws 22 move close to each other, the product can be clamped. When the two clamping jaws 22 move away from each other, the product is released. The clamping driving member 21 in the embodiment is a clamping cylinder. The clamping cylinder is also called a pneumatic finger, pneumatic clamping jaw, or pneumatic clamping finger. It is an execution device for clamping or grabbing workpieces by using compressed air as power. The grabbing unit 2 is a clamping jaw, which can realize grabbing, mounting, and transferring of the product.

[0063] In the embodiment, the grabbing method of the grabbing mechanism is as follows. When the grabbing mechanism grabs the product, the locking part 161 of the locking shaft 16 is connected to the locking hole 141. When the grabbing mechanism releases the product, the releasing part 162 is connected to the locking hole 141.

[0064] Before the grabbing mechanism grabs the product, the locking driving member 15 drives the locking shaft 16 to move along the Z-axis direction, so that the locking part 161 of the locking shaft 16 is located in the locking hole 141. The second support member 14 loses the freedom of movement in the plane relative to the first support member 11.

[0065] The gripping mechanism grips the product, and before assembling or placing down the product, the locking shaft 16 is moved along the Z-axis direction by the locking driving member 15, so that the release part 162 of the locking shaft 16 is just located in the locking hole 141, and the second bracket member 14 has the freedom of moving in the plane relative to the first bracket member 11.

[0066] Obviously, the above embodiments are only examples for clearly illustrating the present application, and are not intended to limit the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, it is not necessary and also impossible to enumerate all the embodiments. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A gripping mechanism, characterized in that, The application relates to a floating locking unit and a grabbing mechanism. The floating locking unit comprises a first support part, an X-axis movement pair, a Y-axis movement pair, a second support part, a locking driving part, a locking shaft and a Z-axis guide part, the second support part is connected to the first support part through the X-axis movement pair and the Y-axis movement pair, the second support part has the freedom of movement in a plane relative to the first support part, the second support part is provided with a locking hole, the locking driving part is connected to the first support part and drives the locking shaft to move along the Z-axis direction, the locking shaft extends along the Z-axis direction and passes through the locking hole, the locking shaft comprises locking parts, releasing parts and transition parts located at different positions along the Z-axis direction, the shaft diameter of the locking parts is the same as the hole diameter of the locking hole, the shaft diameter of the releasing parts is smaller than the hole diameter of the locking hole, the transition parts smoothly connect the locking parts and the releasing parts, the locking parts and the releasing parts are cylindrical, the transition parts are circular truncated cone-shaped, the Z-axis guide part is connected to the first support part, the Z-axis guide part is provided with a guide hole, the locking shaft passes through the guide hole, and the guide hole guides the movement of the locking shaft along the Z-axis direction. The grabbing unit is connected to the second support part and grabs products. The locking shaft comprises two locking parts, one releasing part and two transition parts, and the two ends of the releasing part are connected to the two locking parts through the two transition parts respectively; the Z-axis guide part comprises two guide parts, the two guide parts are located on the two sides of the second support part along the Z-axis direction respectively, the two guide parts are provided with the guide hole respectively, and the two guide holes are connected to the two locking parts respectively.

2. The grasping mechanism of claim 1, wherein, The Z-axis guide part further comprises a connecting part, the connecting part is connected between the two guide parts, and the connecting part is fixed relative to the first support part.

3. The grasping mechanism of claim 1, wherein, The X-axis movement pair comprises an X-axis sliding rail and an X-axis sliding block, the X-axis sliding rail is fixed relative to the first support part, and the X-axis sliding block is slidably connected to the X-axis sliding rail along the X-axis direction; The Y-axis movement pair comprises a Y-axis guide rail and a Y-axis sliding block, the Y-axis guide rail is fixed relative to the X-axis sliding block, the Y-axis sliding block is slidably connected to the Y-axis guide rail along the Y-axis direction, and the second support part is fixed relative to the Y-axis sliding block.

4. The grasping mechanism of claim 3, wherein, The floating locking unit comprises two X-axis movement pairs, two Y-axis movement pairs and two second support parts, each X-axis movement pair comprises one X-axis sliding rail and two X-axis sliding blocks, each Y-axis guide rail is fixed relative to the two X-axis sliding blocks on different X-axis sliding rails, and the two second support parts are fixed relative to the Y-axis sliding blocks of the two Y-axis movement pairs respectively. The grabbing mechanism comprises two grabbing units, and the two grabbing units are connected to the two second support parts respectively.

5. The grasping mechanism of claim 1, wherein, The grabbing unit comprises a clamping driving part and two clamping claws, the clamping driving part is connected to the second support part and drives the two clamping claws to open and close along the Y-axis direction.

6. The gripping method of the gripping mechanism according to any one of claims 1 to 5, characterized in that, When the grabbing mechanism grabs the product, the locking portion is connected with the locking hole in a matched mode; when the grabbing mechanism releases the product, the releasing portion is connected with the locking hole in a matched mode.

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