Gripping mechanism and end effector

Abstract

The gripping mechanism includes a pair of gripping portions including a first gripping portion and a second gripping portion facing each other. The first gripping portion and the second gripping portion each include a first end, a second end on the opposite side of the first end, a protrusion provided at the first end, and a rotation shaft provided at the second end. The protrusion is rotatable about the rotation shaft. The first gripping portion and the second gripping portion face each other in a direction intersecting the direction in which the rotation shaft extends.

Description

Technical Field

[0001] This invention relates to a gripping mechanism and an end effector. Background Technology

[0002] Patent Document 1 discloses a robotic arm. This robotic arm includes a base, a gripping section for gripping an object using a first gripping section and a second gripping section, and a adjusting section. When gripping an object, the adjusting section allows the first and second gripping sections to rotate about an axis extending from the base, and to rotate in an opening / closing direction, with their respective gripping surfaces conforming to the shape of the object. This ensures that the gripping surfaces of the gripping sections accurately conform to the shape of the object.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2012-066368 Summary of the Invention

[0006] The present invention provides a gripping mechanism and an end effector capable of stably gripping an object.

[0007] The gripping mechanism of the present invention includes a pair of gripping portions, including a first gripping portion and a second gripping portion that are opposed to each other. Each of the first and second gripping portions includes: a first end; a second end opposite to the first end; a protrusion disposed at the first end; and a rotation axis disposed at the second end. The protrusion is rotatable about the rotation axis. The first and second gripping portions are opposed to each other in a direction intersecting the direction extending from the rotation axis.

[0008] According to the present invention, a gripping mechanism and an end effector capable of stably gripping an object can be provided. Attached Figure Description

[0009] Figure 1 This is a conceptual diagram showing a robotic arm equipped with an end effector.

[0010] Figure 2 This is a three-dimensional view showing the end effector.

[0011] Figure 3 This is a top view showing the end effector.

[0012] Figure 4 This is a side view showing the end effector.

[0013] Figure 5This is a perspective view showing the first gripping part connected to the connecting member.

[0014] Figure 6 This is an exploded perspective view of the connecting components and the first gripping part.

[0015] Figure 7 This is a perspective view showing the first gripping part connected to the connecting member.

[0016] Figure 8 This is a conceptual diagram showing the first state when the holding mechanism holds the object being held.

[0017] Figure 9 This is a conceptual diagram showing the second state when the holding mechanism holds the object being held.

[0018] Figure 10 This is a conceptual diagram illustrating the third state when the holding mechanism holds the object being held.

[0019] Figure 11 This is a conceptual diagram illustrating the fourth state when the holding mechanism holds the object being held.

[0020] Figure 12 This is a diagram illustrating an example of a holding mechanism holding an object.

[0021] Figure 13 This is a diagram illustrating an example of a holding mechanism holding an object.

[0022] Figure 14 This is a diagram illustrating an example of a holding mechanism holding an object.

[0023] Figure 15 This is a block diagram illustrating an example of the hardware structure of a control device. Detailed Implementation

[0024] (The process of obtaining the present invention)

[0025] Typically, end effectors such as robotic arms are controlled by a control device located at the base, enabling them to grasp objects. Here, the object being grasped is, for example, tableware. Tableware often has a tilted side. Furthermore, the tilt angle varies depending on the object being grasped. Not limited to tableware, end effectors struggle to stably grasp objects with various tilt angles.

[0026] In the robotic hand described in Patent Document 1, the adjusting part is composed of an elastic member. Furthermore, the adjusting part allows the gripping piece to rotate about an axis extending from the base, as well as to rotate in the opening and closing direction. Therefore, when using the two gripping pieces to clamp a cup or the like, the gripping surface of the gripping piece mimics the outer circumference of the cup.

[0027] However, robotic arms still struggle to grip tilted objects, such as shallow dishes. When the gripping force is weak, stable holding of the object is difficult, and there is a possibility of slippage. Conversely, when the gripping force is strong, the object can slide off the gripping force along its tilt, again making stable holding difficult and increasing the possibility of gripping failure. Furthermore, the tilt of the object is not necessarily linear, thus there are situations where sufficient frictional force cannot be generated for the gripping force to stably hold the object.

[0028] Therefore, in the following embodiments, the gripping mechanism and the end effector capable of stably gripping an inclined gripping object will be described in detail.

[0029] Hereinafter, embodiments of the gripping mechanism and end effector of the present invention (hereinafter referred to as "this embodiment") will be described in detail with appropriate reference to the accompanying drawings. However, sometimes the detailed descriptions required above are omitted. For example, detailed descriptions of known matters and repetitive descriptions of substantially the same structures are sometimes omitted. This is to avoid making the following description unnecessarily lengthy and to facilitate understanding by those skilled in the art. It should be noted that the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present invention, and are not intended to limit the subject matter of the technical solution described herein.

[0030] Figure 1 This is a conceptual diagram showing a robotic arm 3 equipped with an end effector 2. The robotic arm 3 typically has a multi-jointed arm. The end effector 2 is mounted at the end of the arm. In this embodiment, the end effector 2 is, for example, a robotic hand with two fingers.

[0031] The gripping mechanism 1 of this embodiment is installed at the front end of the end effector 2. The gripping mechanism 1 grips, for example, a gripping object OBJ such as tableware. However, the gripping object OBJ is not limited to tableware.

[0032] Figure 2 This is a perspective view showing the end effector 2. Figure 3 This is a top view showing the end effector 2. Figure 4 This is a side view showing the end effector 2. (Refer to...) Figures 2 to 4 The end effector 2, on which the holding mechanism 1 is mounted, will be described.

[0033] For ease of explanation, coordinate axes are used. The coordinate axes shown in the diagram are those of an orthogonal coordinate system with mutually orthogonal X, Y, and Z axes. The end effector 2 includes a base 23, a first finger 21, and a second finger 22. The first finger 21 and the second finger 22 are mounted on the base 23 in a manner that allows them to rotate about an axis parallel to the Z-axis shown in the diagram.

[0034] The gripping mechanism 1 includes a first gripping portion 11 and a second gripping portion 12. The first gripping portion 11 and the second gripping portion 12 are opposite to each other. That is, the gripping mechanism 1 has a pair of gripping portions (e.g., the first gripping portion 11 and the second gripping portion 12) that are opposite to each other. The first gripping portion 11 and the second gripping portion 12 each have a rotation axis 111 and 121, respectively. The rotation axis 111 extends toward the front end of the first finger 21. The rotation axis 121 extends toward the front end of the second finger 22. In the illustrated example, the rotation axis 111 and the rotation axis 121 extend along the X-axis, respectively. The first gripping portion 11 is rotatable about the rotation axis 111. The second gripping portion 12 is rotatable about the rotation axis 121. The first gripping portion 11 and the second gripping portion 12 are opposite to each other in a direction that intersects the direction in which the rotation axis 111 and the rotation axis 121 extend. In the illustrated example, the first gripping part 11 and the second gripping part 12 are positioned opposite each other along the Y-axis, which is orthogonal to the X-axis direction, which extends as the rotation axes 111 and 121. It should be noted that, regarding... Figures 2 to 4 The torsion springs 116 and 126 shown respectively are based on Figures 5 to 7 The following will be described.

[0035] A connecting member 51 is disposed between the first gripping portion 11 and the first finger 21. The connecting member 51 connects the first gripping portion 11 and the first finger 21. A connecting member 52 is disposed between the second gripping portion 12 and the second finger 22. The connecting member 52 connects the second gripping portion 12 and the second finger 22. The connecting members 51 and 52 are respectively configured such that, when viewed from the Z-axis direction (refer to...),... Figure 3 It is a plate-shaped structure with three bent sides. However, the shapes of connecting members 51 and 52 are not limited to this.

[0036] The first gripping part 11 is connected to one end of the connecting member 51. More specifically, the rotating shaft 111 of the first gripping part 11 is inserted into and fixed in a hole provided at one end of the connecting member 51. The second gripping part 12 is connected to one end of the connecting member 52. More specifically, the rotating shaft 121 of the second gripping part 12 is inserted into and fixed in a hole provided at one end of the connecting member 52.

[0037] The other end of the connecting member 51 is fixed to the connecting portion C1 protruding from the first finger 21. The other end of the connecting member 52 is fixed to the connecting portion C2 protruding from the second finger 22. The connecting portion C1 is mounted on the two fulcrums of the first finger 21 (see reference) in a manner that allows it to rotate along an axis parallel to the Z-axis in the figure. Figure 3 The connecting part C2 is mounted on the two fulcrums of the second finger 22 in a manner that allows it to rotate along an axis parallel to the Z-axis in the figure (see reference). Figure 3 Therefore, even when the first finger 21 and the second finger 22 open and close, the connecting part C1 and the connecting part C2 remain parallel to each other.

[0038] It should be noted that the connecting member 51 and connecting member 52 may not be provided in the end effector 2. In this case, the first gripping part 11 and the second gripping part 12 can be directly fixed to the first finger 21 and the second finger 22, respectively.

[0039] Figure 5 This is a perspective view showing the first gripping part 11 connected to the connecting member 51. Figure 6 This is an exploded perspective view of the connecting member 51 and the first gripping part 11. Figure 7 This is a perspective view showing the first gripping part 11 connected to the connecting member 51. See also... Figures 5 to 7 The structure of the first gripping part 11 will be described. It should be noted that the structure of the second gripping part 12 is the same as that of the first gripping part 11, except that the first gripping part 11 and the second gripping part 12 are opposite to each other. Therefore, the description of the structure of the first gripping part 11 can also be applied, and detailed description is omitted.

[0040] The first gripping part 11 includes a rotating shaft 111, a first frame 112, a second frame 113 as an example of a frame, a third frame 114 as an example of a frame, a rigid body limiter 115, and a torsion spring 116.

[0041] The first frame 112 has a generally bent planar shape. One end of the first frame 112 is bent in a generally "U" shape so as to enclose the rotation axis 111 along the X-axis direction. The other end of the first frame 112 is bent in a generally L-shape so as to ride on the rigid body limiter 115 described later along the X-direction. That is, the first frame 112 is connected to the rigid body limiter 115 and the rotation axis 111.

[0042] The second frame 113 and the third frame 114 have a curved rod shape. The second frame 113 has a perforated ring 1131. The third frame 114 has a perforated ring 1141. Perforated rings 1131 and 1141 are respectively provided at one end of the second frame 113 and the third frame 114. The rotating shaft 111 passes through the perforated rings 1131 and 1141 respectively.

[0043] The rotating shaft 111 also passes through the torsion spring 116. The torsion spring 116 can be... Figure 6 The configuration shown is between the third frame 114 and the connecting member 51. The torsion spring 116 can be as follows: Figure 3 as well as Figure 7 It is arranged as depicted between the second frame 113 and the third frame 114.

[0044] One end of the torsion spring 116 is fixed to the rotating shaft 111, and the other end of the torsion spring 116 is fixed to the third frame 114. Therefore, the first gripping part 11 rotates around the rotating shaft 111 when subjected to external force, but when the external force disappears, the first gripping part 11 returns to its original position under the force of the torsion spring 116 fixed at one end to the rotating shaft 111.

[0045] The rigid body limiter 115 has a roughly "U" shape. One end of the rigid body limiter 115 is inserted into the end of the second frame 113 opposite to the end of the perforated ring 1131 (see reference). Figure 5 or Figure 7 The other end of the rigid body limiter 115 is inserted into the end of the third frame 114 opposite to the end of the perforated ring 1141 (see reference). Figure 5 or Figure 7 Thus, the central portion of the rigid body limiter 115 forms a protrusion at the first end of the first gripping portion 11. For example... Figure 7 As shown, the rigid body limiter 115 is disposed between the second frame 113 and the third frame 114. Furthermore, the first frame 112, the second frame 113, the third frame 114, and the rigid body limiter 115 are all capable of rotating around the rotation axis 111. It should be noted that in this embodiment, the first end of the first gripping part 11 faces the side in the Z-axis direction shown in the figure. The second end of the first gripping part 11 faces the side in the direction opposite to the Z-axis direction shown in the figure.

[0046] A buffer 117 is provided in the first gripping part 11. The buffer 117 is provided on one side of the gripping part 12, which faces the opposite side of the rotation axis 111. In this embodiment, the buffer 117 is provided on the Y-axis direction side of the rotation axis 111. Additionally, as... Figure 5As shown, a buffer 117 is disposed between the first frame 112 and the elastic sheet 118. By providing the buffer 117 in the first grip portion 11, the gripping mechanism 1 can receive the object being gripped (e.g., tableware) in a shape-matching manner, thus enabling stable gripping of the object. Furthermore, by providing the buffer 117 at the aforementioned position of the first grip portion 11 (i.e., on the side of the grip portion facing the opposite direction of the rotation axis 111, i.e., the second grip portion 12), external forces received by the buffer 117 from the object being gripped will not cause the first grip portion 11 to rotate around the rotation axis 111. Therefore, when gripping an object (especially a cylindrical object such as a cup), the relative position of the first grip portion 11 with respect to the object does not shift along the rotation direction of the first grip portion 11. Consequently, the gripping mechanism 1 can further stabilize the gripping of the object.

[0047] It should be noted that in this embodiment, the buffer 117 is disposed between the first frame 112 and the elastic sheet 118 (described later). Therefore, the buffer 117 can press the elastic sheet 118 against the object being held. As a result, the area of ​​the elastic sheet 118 and the object being held is large, allowing for a larger gripping surface on the object. This increases the stability of the gripping action performed by the first gripping part 11.

[0048] An elastic sheet 118 is provided on one side of the second gripping part 12, which is the opposite gripping part of the first gripping part 11. The elastic sheet 118 is formed of a deformable component, such as silicone. In this embodiment, the elastic sheet 118 is fixed to the end of the first frame 112 on the side of the rotation axis 111 and the end on the side of the rigid body limiter 115. In addition, as described above, a buffer 117 is provided between the elastic sheet 118 and the first frame 112 at the end on the side of the rotation axis 111, and a clearance space is generated on the side of the rigid body limiter 115. This clearance space becomes the deformation space of the elastic sheet 118 and absorbs the difference in the side shape of the object to be gripped, such as a shallow plate or a deep plate, and matches the shape of the object to be gripped. That is, the elastic sheet 118 is more easily deformed on the side of the rigid body limiter 115 than on the side of the rotation axis 111, depending on the presence or absence of the buffer 117.

[0049] With the structure described above, the gripping mechanism 1 can grip the object being gripped by facing it, thus ensuring stable gripping of the object. Furthermore, the elastic sheet 118 is in close contact with the object being gripped, thus providing even more stable gripping.

[0050] Preferably, the friction on the first end side of the elastic sheet 118 near the first end of the first gripping portion 11 is less than the friction on the second end side near the second end of the first gripping portion 11. Therefore, the object being gripped, in contact with the elastic sheet 118, can easily move towards the rigid body retainer 115. Furthermore, the second end side of the first gripping portion 11 in the elastic sheet 118 is less prone to sliding than the first end side. Therefore, the object being gripped can be held using the less prone second end side. It should be noted that in this embodiment, a low-friction sheet 119 is attached to the first end side of the first gripping portion 11 in the elastic sheet 118, i.e., the side near the rigid body retainer 115. The friction of the low-friction sheet 119 is less than the friction of the elastic sheet 118. However, the method of setting a difference in friction between the first end side and the second end side of the first gripping portion 11 in the elastic sheet 118 is not limited to this. For example, the elastic sheet 118 itself can be constructed using a low-friction sheet. Furthermore, a piece with higher friction can be attached to the second end side of the first gripping part 11 in the low-friction elastic sheet 118, or an anti-slip processing can be performed.

[0051] It should be noted that when referring to together Figure 7 At position 12, the second frame 113 has a first end connected to the rigid body limiter 115 and a second end connected to the rotation axis 111. The first end of the first gripping portion 11 in the second frame 113 and the third frame 114 is bent toward the opposite gripping portion (i.e., the second gripping portion 12). In this embodiment, the second frame 113 and the third frame 114 are bent in a "U" shape, for example. Thus, compared to the case where the second frame 113 and the third frame 114 are formed in a straight line like an "I", the protrusion (e.g., the rigid body limiter 115) tilts toward the object being gripped and has a positional relationship parallel to the object being gripped. Therefore, when the object being gripped slides upward (in the Z-axis direction in the figure) during gripping by the gripping mechanism 1, the object being gripped is prevented from detaching from the protrusion (e.g., the rigid body limiter 115).

[0052] Figure 8 This is a conceptual diagram showing the first state when the holding mechanism 1 holds the object OBJ. Figure 9 This is a conceptual diagram showing the second state when the holding mechanism 1 holds the object OBJ. Figure 10 This is a conceptual diagram showing the third state when the holding mechanism 1 holds the object OBJ. Figure 11 This is a conceptual diagram illustrating the fourth state when the gripping mechanism 1 grips the object OBJ. Based on... Figures 8 to 11 The control of object OBJ by control mechanism 1 will be explained.

[0053] Here, the second gripping part 12 of the gripping mechanism 1 has the same structure as the first gripping part 11, except that the first gripping part 11 and the second gripping part 12 are opposite to each other. The reference numerals for the components in the second gripping part 12 that are the same as those in the first gripping part 11 are respectively designated as rotation shaft 121, first frame 122, second frame 123, third frame 124, rigid body limiter 125, torsion spring 126, buffer member 127, elastic plate 128, and low-friction plate 129. (See attached figures.) Figure 8 As shown, the buffer 117 of the first gripping part 11 and the buffer 127 of the second gripping part 12 are disposed between the rotation axis 111 of the first gripping part 11 and the rotation axis 121 of the second gripping part 12. In addition, the elastic sheet 118 of the first gripping part 11 and the elastic sheet 128 of the second gripping part 12 are opposite to each other in a direction (e.g., the Y-axis direction) that intersects the direction of extension of the rotation axes 111 and 121 (e.g., the X-axis direction).

[0054] exist Figure 8 The diagram shows the first state when the holding mechanism 1 holds the object OBJ. The control device 100, described later, controls the end effector 2 to gradually bring the first holding portion 11 and the second holding portion 12 of the holding mechanism 1 closer to the outside (i.e., the outer periphery) of the object OBJ. It should be noted that the object OBJ in this embodiment is tableware. This tableware is a truncated cone shape, such as a ramen bowl (in other words, a ramen basin), which has a diameter that increases towards the top (Z-axis direction in the figure). However, as described later, the holding mechanism 1 can also hold objects of other shapes.

[0055] exist Figure 9 The diagram shows the second state when the gripping mechanism 1 grips the object OBJ. The control device 100, described later, controls the end effector 2 to press the first gripping part 11 and the second gripping part 12 of the gripping mechanism 1 against the outer side (i.e., the outer peripheral side) of the object OBJ. Then, firstly, the elastic plates 118 and 128 and the low-friction plates 119 and 129 come into contact with the largest diameter portion of the object OBJ (refer to the arrows labeled P1 and P2 in the diagram).

[0056] The control device 100, described later, controls the end effector 2 to further press the first gripping portion 11 and the second gripping portion 12 of the gripping mechanism 1 against the outer side (i.e., the outer peripheral side) of the object to be gripped, OBJ. As a result, the elastic plates 118 and 128, and the low-friction plates 119 and 129 deform and conform to the shape of the side surface of the object to be gripped, OBJ. The portions of the elastic plates 118 and 128, and the low-friction plates 119 and 129 near the buffer members 117 and 127, come into contact with the side surface of the object to be gripped, OBJ.

[0057] exist Figure 10 The figure shows the third state of the gripping mechanism 1 gripping the object OBJ. The control device 100, described later, controls the end effector 2 to further press the first gripping part 11 and the second gripping part 12 of the gripping mechanism 1 against the outer side (i.e., the outer periphery) of the object OBJ. Thus, the first gripping part 11 and the second gripping part 12 overcome the forces of the torsion springs 116 and 126, and rotate outwards about the rotation axes 111 and 121, respectively. In the figure, the rotation axes 111 and 121 extend along the X-axis. The rotation directions of the first gripping part 11 and the second gripping part 12 are indicated by arrows labeled R1 and R2 in the figure.

[0058] The object OBJ is held between two sides by buffers 117 and 127, elastic plates 118 and 128, and low-friction plates 119 and 129. Here, the low-friction plates 119 and 129 have low friction, so when the first gripping part 11 and the second gripping part 12 are further pressed against the outer side (i.e., the outer peripheral side) of the object OBJ, the object OBJ slides along its incline. Therefore, the object OBJ moves in the direction where the rigid body limiters 115 and 125 are located. In the illustrated example, the object OBJ moves in the Z-axis direction shown in the figure. This state after movement is... Figure 11 As shown in the image.

[0059] exist Figure 11 The diagram shows the fourth state when the gripping mechanism 1 grips the object OBJ. The edge of the object OBJ is in contact with the rigid body limiters 115 and 125, preventing further movement in the Z-axis direction. Therefore, the object OBJ is clamped and stably gripped by the members disposed on the first end sides of the first gripping portion 11 and the second gripping portion 12, and on the second end sides of the first gripping portion 11 and the second gripping portion 12, respectively. The members disposed on the first end sides of the first gripping portion 11 and the second gripping portion 12 are the rigid body limiters 115 and 125. The members disposed on the second end sides of the first gripping portion 11 and the second gripping portion 12 are the buffer members 117 and 127, the elastic sheet 118 and 128, and the low-friction sheet 119 and 129.

[0060] Figure 12 This is a diagram showing an example of how the holding mechanism 1 holds the object OBJ. Figure 13 This is a diagram showing an example of how the holding mechanism 1 holds the object OBJ. Figure 14 This is a diagram showing an example of how the holding mechanism 1 holds the object OBJ.

[0061] The holding mechanism 1 in this embodiment is as follows: Figure 12 as well as Figure 13 As shown, various objects OBJ with different heights and side shapes can be stably held. This is because the rigid body limiters 115 and 125, located on the upper side of the figure, hold the object OBJ along a line (i.e., a straight line along the X-axis). The lower portions of the elastic plates 118 and 128, as well as the buffers 117 and 127, are held in a surface manner that matches the shape of the object OBJ. Furthermore, even when the side of the object OBJ is not straight, the elastic plates 118 and 128 deform along the side shape of the object OBJ, thus allowing them to fit snugly against the object OBJ and stably hold it.

[0062] Furthermore, the holding mechanism 1 in this embodiment can also be as follows: Figure 14 As shown, the object OBJ, which is roughly cylindrical and not tilted to the side, is held stably. The portions of elastic sheets 118 and 128 closest to buffers 117 and 127 have high friction. Therefore, buffers 117 and 127 press elastic sheets 118 and 128 against the object OBJ, thereby stably holding the object OBJ under the action of friction.

[0063] Furthermore, although the illustration is omitted, the holding mechanism 1 of this embodiment can also hold objects that are shaped like a frustum, such as an inverted ramen bowl, and whose diameter decreases as it moves upward.

[0064] In addition to holding the holding mechanism 1 in this embodiment, it can also hold various other objects such as kettles, planters, beer bottles, liters, fire extinguishers, paper bags, and PET bottles.

[0065] The gripping mechanism 1 of this embodiment is particularly capable of gripping objects that are placed on the ground and have an oblique shape. Such obliquely shaped objects were previously difficult to grip.

[0066] Figure 15 This is a block diagram illustrating an example of the hardware structure of the control device 100. The control device 100 includes a processor 101, a memory 102, an input device 103, an end effector connection unit 105, a communication device 106, and an input / output interface 107.

[0067] The processor 101 is configured using, for example, a CPU (Central Processing Unit), MPU (Micro Processing Unit), GPU (Graphical Processing Unit), DSP (Digital Signal Processor), or FPGA (Field Programmable Gate Array). The processor 101, in cooperation with the memory 102, performs various processing and control operations within the control device 100. For example, the processor 101 receives various feedback information from the end effector 2 via the end effector connection 105, generates a control signal to control the operation of the end effector 2, and sends the control signal to the end effector 2.

[0068] Memory 102 includes, for example, RAM (Random Access Memory) used as working memory when executing the processing of processor 101, and ROM (Read Only Memory) storing programs that define the processing of processor 101. Data generated or retrieved by processor 101 is temporarily stored in RAM. Programs defining the processing of processor 101 are written into ROM. Memory 102 may store action content information, which defines the actions that the end effector 2 should perform. The action content information may include, for example, programs for the end effector 2 to perform certain actions.

[0069] Input device 103 is a device for allowing a user to input information. Specifically, input device 103 may be a keyboard, mouse, teach pendant, etc. Input device 103 may also be a device other than a keyboard, mouse, or teach pendant.

[0070] The end effector connection unit 105 is configured using an input / output circuit that connects the end effector 2 to the control device 100. Information is transmitted between the end effector 2 and, for example, the processor 101.

[0071] The communication device 106 has the usual functions for communicating information with external devices via a communication network 108, such as the Internet.

[0072] The input / output interface 107 is sandwiched between the memory 102, the input device 103, the end effector connection part 105, the communication device 106 and the processor 101, and has the function of inputting and outputting data between them.

[0073] It should be noted that the control device 100 may also include components other than those described above.

[0074] As described above, the gripping mechanism 1 of this embodiment includes a pair of gripping portions (specifically, a first gripping portion 11 and a second gripping portion 12) facing each other. Each of the first gripping portions 11 and the second gripping portion 12 has a protrusion (specifically, rigid body limiters 115 and 125) at its first end. Each of the first gripping portions 11 and the second gripping portion 12 is rotatable about a rotation axis 111 or 121 located at a second end opposite to the first end of each of the first gripping portions 11 and the second gripping portion 12. The first gripping portions 11 and the second gripping portion 12 are facing each other in a direction intersecting the direction extending from the rotation axes 111 and 121. Therefore, the gripping mechanism 1 allows the first gripping part 11 and the second gripping part 12 to slide relative to the object OBJ, and uses the protrusions (rigid body limiters 115, 125) to clamp the object OBJ with the first gripping part 11 and the second gripping part 12. Thus, the gripping mechanism 1 can stably grip the object OBJ.

[0075] Furthermore, each of the first gripping portions 11 and the second gripping portion 12 is provided with corresponding buffers 117 and 127. The buffers 117 and 127 are each arranged along a direction parallel to their respective rotation axes 111 and 121, and on a side facing the opposite second gripping portion 12 and first gripping portion 11. Thus, the gripping mechanism 1 can gently receive the object OBJ, thereby stably gripping the object OBJ. Furthermore, the external force received by the buffers 117 and 127 from the object OBJ will not cause the first gripping portions 11 and second gripping portions 12 to rotate around the rotation axes 111 and 121. Therefore, during gripping, the relative position of the first gripping portions 11 and second gripping portions 12 with respect to the object OBJ will not shift in the direction of rotation. Therefore, the gripping mechanism 1 can further stably grip the object OBJ.

[0076] Furthermore, each of the first gripping part 11 and the second gripping part 12 has corresponding elastic pieces 118 and 128 on the side facing the opposite side of the second gripping part 12 and the first gripping part 11. As a result, the elastic pieces 118 and 128 are in close contact with the object OBJ being gripped, so the gripping mechanism 1 can further stabilize the object OBJ being gripped.

[0077] Furthermore, in each of the pair of first gripping portions 11 and second gripping portions 12, the first end side of each of the first gripping portions 11 and second gripping portions 12 is smaller than the second end side opposite to the first end side in terms of friction with the elastic sheets 118 and 128. As a result, the object OBJ is more likely to move toward the protrusion (specifically, the rigid body limiters 115 and 125), and the gripping mechanism 1 can further stabilize the gripping object OBJ.

[0078] Furthermore, a protrusion (e.g., a rigid body limiter 115) is provided on a second frame 113 and a third frame 114 having perforated rings 1131 and 1141 through which a rotation shaft 111 passes. The first end of the first gripping portion 11 in the second frame 113 and the third frame 114 is bent toward the opposite second gripping portion 12. As a result, the protrusion (e.g., the rigid body limiter 115) tilts toward the object being gripped. Therefore, if the object being gripped slides upward (in the Z-axis direction), it is prevented from detaching from the protrusion (e.g., the rigid body limiter 115).

[0079] Furthermore, the end effector 2 includes the aforementioned gripping mechanism 1. Thus, an end effector 2 capable of stably gripping the object OBJ can be provided.

[0080] The various embodiments have been described above with reference to the accompanying drawings, but the present invention is not limited to these examples. Those skilled in the art will obviously be able to conceive of various modifications, alterations, substitutions, additions, deletions, and equivalents within the scope of the technical solutions described, and these are naturally understood to fall within the technical scope of the present invention. Furthermore, the constituent elements of the various embodiments described above can be combined arbitrarily without departing from the spirit of the invention.

[0081] Industrial applicability

[0082] The present invention is useful as a gripping mechanism and end effector capable of stably gripping an object.

[0083] Explanation of reference numerals in the attached figures

[0084] 1. Controlling Institutions

[0085] 2. End effector

[0086] 3. Robotic Arm

[0087] 11 First Control Department

[0088] 12 Second Control Department

[0089] 21 First finger

[0090] 22 Second finger

[0091] 23 Base

[0092] 51, 52 Connecting components

[0093] 100 Control device

[0094] 101 processor

[0095] 102 Memory

[0096] 103 Input Device

[0097] 105 End effector connection part

[0098] 106 Communication devices

[0099] 107 Input / Output Interfaces

[0100] 108 Communication Network

[0101] Rotating axes 111 and 121

[0102] 112, 122 First Frame

[0103] 113, 123 Second Frame

[0104] 114, 124 Third Frame

[0105] 115, 125 Rigid Body Limiters

[0106] 116, 126 Torsion Springs

[0107] 117, 127 Buffer

[0108] 118, 128 elastic sheets

[0109] 119, 129 Low Friction Plates

[0110] 1131, 1141 Opening rings.

Claims

1. A holding mechanism, wherein, The gripping mechanism has a pair of gripping parts, including a first gripping part and a second gripping part that are opposed to each other. The first gripping part and the second gripping part each have: First end; The second end, located on the opposite side of the first end; A protrusion is provided at the first end; A rotating shaft is disposed at the second end; A first frame is connected to the protrusion and the rotation axis; A buffer element is disposed on the first frame; as well as An elastic sheet is disposed on the buffer member. The protrusion is capable of rotating about the rotation axis. The first gripping part and the second gripping part are positioned opposite each other in a direction that intersects the direction in which the rotation axis extends. When the relative positions of the first gripping part and the second gripping part change, the relative positions of the rotation axes of the first gripping part and the second gripping part also change. The protrusions of the first gripping part and the second gripping part protrude in a direction opposite to the first gripping part and the second gripping part, respectively. The buffer is disposed between the first frame and the elastic sheet.

2. The holding mechanism according to claim 1, wherein, The elastic sheet has a first end side near the first end and a second end side near the second end. The friction at the first end of the elastic sheet is less than the friction at the second end of the elastic sheet.

3. The holding mechanism according to claim 1, wherein, The elastic sheet has a first end side near the first end and a second end side near the second end. The elastic sheet includes a friction sheet attached to a first end side of the elastic sheet and having a friction lower than that of the elastic sheet.

4. A holding mechanism, wherein, The gripping mechanism has a pair of gripping parts, including a first gripping part and a second gripping part that are opposed to each other. The first gripping part and the second gripping part each have: First end; The second end, located on the opposite side of the first end; A protrusion is provided at the first end; A rotating shaft is disposed at the second end; A first frame is connected to the protrusion and the rotation axis; A buffer element is disposed on the first frame; as well as An elastic sheet is disposed on the buffer member. The protrusion is capable of rotating about the rotation axis. The first gripping part and the second gripping part are positioned opposite each other in a direction that intersects the direction in which the rotation axis extends. The protrusions of the first gripping part and the second gripping part protrude in a direction opposite to the first gripping part and the second gripping part, respectively. The first gripping part and the second gripping part each also have a second frame, the second frame having an opening ring through which the rotating shaft passes and being connected to the protrusion. The second frame has a first end side connected to the protrusion and a second end side connected to the rotation axis. The first end side of the second frame of the first gripping part is bent toward the second gripping part. The buffer is disposed between the first frame and the elastic sheet.

5. The holding mechanism according to claim 4, wherein, The first gripping part and the second gripping part each also have a third frame, the third frame having an opening ring through which the rotating shaft passes and being connected to the protrusion. The third frame has a first end side connected to the protrusion and a second end side connected to the rotation axis. The first end side of the third frame of the first gripping part is bent toward the second gripping part. The protrusion is disposed between the second frame and the third frame.

6. An end effector, wherein, The end effector has the gripping mechanism as described in any one of claims 1 to 5.

7. The end effector according to claim 6, wherein, The end effector also features: The first finger is connected to the first gripping part; The second finger is connected to the second gripping part; as well as The base, which is connected to the first finger and the second finger, The first finger and the second finger are each capable of rotating relative to the base with an axis orthogonal to the direction extending from the rotation axis.

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