robotic arm

Abstract

This invention provides a robotic hand. The robotic hand (100) includes a first finger (2) and a second finger (3) and a first moving mechanism (5). The first moving mechanism (5) causes the first finger (2) and the second finger (3) to approach each other in a predetermined moving direction, so that the first finger (2) and the second finger (3) grasp a workpiece. The first moving mechanism (5) has a first movable pulley (53), a first metal wire (56), and a first cylinder (57). The first metal wire (56) has two ends and is wound around the first movable pulley (53). The two ends are connected to each of the first finger (2) and the second finger (3). The first cylinder (57) causes the first movable pulley (53) to move. The first cylinder (57) causes the first movable pulley (53) to move so that the tension of the first metal wire (56) acts on the first finger (2) and the second finger (3), causing the first finger (2) and the second finger (3) to approach each other.

Description

Technical Field

[0001] This invention relates to a robotic hand. Background Technology

[0002] To date, robotic hands capable of so-called contour-grasping of workpieces are well known. For example, a robotic hand disclosed in Patent Document 1 includes a pair of fingers, a motor, and a differential gear mechanism. The pair of fingers grip the workpiece, the motor causes the pair of fingers to move, and the differential gear mechanism transmits the motor's power to the pair of fingers. According to this robotic hand, when the workpiece deviates from the center of the robotic hand, the finger closer to the workpiece (one finger) contacts the workpiece first and then stops. Even if one finger stops, the other finger continues to move and then contacts the workpiece and stops. Contour-grasping of the workpiece is performed in this way.

[0003] Patent Document 1: Japanese Patent Application Publication No. 62-99094 Summary of the Invention

[0004] However, in the hands of the robot, due to the use of a differential gear mechanism, there is a problem that the movement of one finger lacks smoothness after the other finger stops.

[0005] In view of the above, the technical objective of this invention is to provide a robotic hand capable of smooth, contour-based gripping.

[0006] The present invention relates to a robotic hand comprising a first finger and a second finger, and a first moving mechanism. The first moving mechanism brings the first and second fingers closer together in a predetermined direction of movement, enabling them to grasp a workpiece. The first moving mechanism includes a first movable pulley, a first cable-like component, and a first actuator. The first cable-like component has two ends that are wound around the first movable pulley, and these two ends are connected to each of the first and second fingers. The first actuator moves the first movable pulley. The movement of the first movable pulley causes the tension of the first cable-like component to act on the first and second fingers, bringing them closer together.

[0007] In the above-described technique, corresponding to the amount of movement of the first movable pulley caused by the first actuator, the first finger and the second finger are respectively pulled and moved by the first cable-like component. More specifically, when the first movable pulley moves via the first actuator, the tension of the first cable-like component acts on the first and second fingers, causing them to move towards each other. As a result, the first and second fingers approach each other, gripping the workpiece W from the outside. At this time, the amount of movement of the first and second fingers, corresponding to the amount of movement of the first movable pulley, is appropriately adjusted based on the resistance to the movement of the first finger and the resistance to the movement of the second finger. For example, when the first finger contacts the workpiece W, if the resistance to the movement of the first finger increases, for example, the first finger stops, and the amount of movement of the second finger appropriately increases. Therefore, the second finger can continue to move smoothly toward the workpiece W. As a result, the workpiece W can be reached by the second finger, allowing for a smooth contour grip.

[0008] Other technologies disclosed in this invention include a robotic hand comprising a first finger, a second finger, and a second moving mechanism. The second moving mechanism separates the first and second fingers from each other in a predetermined direction of movement, allowing the first and second fingers to grasp a workpiece. The second moving mechanism has a second movable pulley, a second cable-like component, and a second actuator. The second cable-like component has two ends that are wound around the second movable pulley, and these two ends are connected to each of the first and second fingers. The second actuator moves the second movable pulley. The second actuator moves the second movable pulley so that the tension of the second cable-like component acts on the first and second fingers, separating them from each other.

[0009] In the above-described technique, corresponding to the amount of movement of the second movable pulley caused by the second actuator, the first finger and the second finger are respectively pulled and moved by the second cable-like component. More specifically, when the second movable pulley moves via the second actuator, the tension of the second cable-like component acts on the first and second fingers, causing them to move in a direction of separation. As a result, the first finger 2 and the second finger 3 separate from each other, gripping the workpiece W from the inside. At this time, the amount of movement of the first finger and the second finger corresponding to the amount of movement of the second movable pulley 65 are appropriately adjusted according to the resistance to the movement of the first finger and the resistance to the movement of the second finger. For example, when the first finger contacts the workpiece W, if the resistance to the movement of the first finger increases, for example, the first finger stops, and the amount of movement of the second finger increases appropriately. Therefore, the second finger can continue to move smoothly toward the workpiece W. As a result, the workpiece W can be reached by the second finger, and a contour grip can be performed smoothly.

[0010] (Invention Effects)

[0011] The robotic hand is capable of performing contour-following grips smoothly. Attached Figure Description

[0012] Figure 1 This is a schematic diagram showing a robotic hand attached to a robotic arm.

[0013] Figure 2 The front view of the robot hand is shown in a simplified manner with the front panel omitted.

[0014] Figure 3 This is a rough left-side view of the robot hand.

[0015] Figure 4 This is a rough view of the right side of the robot hand.

[0016] Figure 5 This is a rough top view of the robot hand with the top plate omitted.

[0017] Figure 6 This diagram shows the first to third movable pulleys and the first cylinder from the right side.

[0018] Figure 7 The diagram shows the first to third movable pulleys in an enlarged view.

[0019] Figure 8 yes Figure 7 The cross-sectional view of line AA shown.

[0020] Figure 9 This is a schematic three-dimensional view showing the wiring in the first moving mechanism.

[0021] Figure 10 This is a schematic three-dimensional view showing the wiring in the second moving mechanism.

[0022] Figure 11 This is a block diagram showing the structure of the control device.

[0023] Figure 12 This is a schematic diagram showing a state of a closed gripping action performed by the first moving mechanism.

[0024] Figure 13 This diagram shows the state of the third movable pulley at the start of the closing grip action.

[0025] Figure 14 This is a schematic diagram showing a state of a closed gripping action performed by the first moving mechanism.

[0026] Figure 15 This is a schematic diagram showing the state after the closing gripping action performed by the first moving mechanism is completed.

[0027] Figure 16 This is a diagram showing the state of the third movable pulley during the centering motion.

[0028] Figure 17 This diagram shows the state of the third movable pulley when the centering action is completed.

[0029] Figure 18 This is a schematic diagram showing the state of the first moving mechanism when the centering action is completed.

[0030] Figure 19 This is a schematic diagram showing one state of the opening and gripping action performed by the second moving mechanism.

[0031] Figure 20 This is a schematic diagram showing one state of the opening and gripping action performed by the second moving mechanism.

[0032] Figure 21 This is a schematic diagram showing the state when the opening and gripping action performed by the second moving mechanism is completed.

[0033] Figure 22 This is a schematic diagram showing the state of the second moving mechanism when the centering action is completed.

[0034] Figure 23 This is a schematic diagram illustrating the structure of the second moving mechanism involved in other embodiments.

[0035] Figure 24 This is a diagram illustrating the state of the third movable pulley involved in other embodiments of the centering operation.

[0036] Figure 25 This is a diagram showing the state of the third movable pulley in other embodiments when the centering action is completed. Detailed Implementation

[0037] Hereinafter, with reference to the accompanying drawings, the exemplary embodiments will be described in detail.

[0038] like Figure 1 As shown, the robot hand 100 (hereinafter, simply referred to as hand 100) in this embodiment is an end effector connected to the front end of the robot arm 10. The robot arm 10 is, for example, a multi-joint arm with multiple links connected in series, and is provided in vertical multi-joint robots, etc. The hand 100 is rotatably connected to the robot arm 10, for example.

[0039] Here, the direction and position mentioned regarding hand 100 refer to the direction and position of the extended direction of the pair of fingers (first finger 2 and second finger 3) in the state where the direction is consistent with the up and down direction, that is, it is Figure 1The orientation and position in the shown state. And, will Figure 2 The left and right directions in the middle are called the width direction of base 1. Figure 3 and Figure 4 The left and right directions in the middle are called the depth directions of base 1.

[0040] Hand 100 is configured to perform a so-called contour grip on a workpiece. Contouring grip occurs when the resistance to the movement of one of a pair of fingers (first finger 2 and second finger 3) increases, causing the other finger to move more to grip the workpiece. For example, even if one finger contacts the workpiece first and then stops, the other finger can continue to move without stopping, thereby contacting and gripping the workpiece.

[0041] Specifically, for example Figures 2-6 As shown, the hand 100 includes a base 1, a first finger 2 and a second finger 3, a support 4, a first moving mechanism 5, a second moving mechanism 6, a first adjusting mechanism 7, and a control mechanism 8. It should be noted that... Figure 3 In the text, the third cylinder 77 of the first adjustment mechanism 7 is omitted.

[0042] The base 1 is the part connected to the robot arm 10, and its outline is roughly rectangular. The vertical direction of the base 1 is its length direction. The base 1 has a front plate 11, a rear plate 12, and an upper plate 13. The front plate 11 and the rear plate 12 have the same shape and face each other. The upper plate 13 is disposed above the front plate 11 and the rear plate 12, connecting the front plate 11 and the rear plate 12.

[0043] Furthermore, a middle plate 14 is provided on the base 1. The middle plate 14 divides the internal space enclosed by the front plate 11, the rear plate 12, and the upper plate 13 in the vertical direction. That is, the middle plate 14 divides the internal space into an upper space and a lower space. The middle plate 14 is positioned close to the upper plate 13 in the internal space, and the upper space is smaller than the lower space.

[0044] The first finger 2 and the second finger 3 are the gripping parts for holding the workpiece. It should be noted that the first finger 2 and the second finger 3 are sometimes referred to as two fingers 2 and 3.

[0045] Each of the first finger 2 and the second finger 3 is a generally rod-shaped component extending in the vertical direction. The first finger 2 and the second finger 3 have the same shape. The first finger 2 and the second finger 3 are arranged parallel to each other. The direction in which the first finger 2 and the second finger 3 are arranged is the width direction of the base 1. The first finger 2 and the second finger 3 have a shape that is linearly symmetrical about the lines extending in the vertical direction (length direction). More specifically, the first finger 2 and the second finger 3 have bases 21 and 31 and finger bodies 22 and 32. The bases 21 and 31 are plate-shaped components extending in the horizontal direction. The finger bodies 22 and 32 extend downwards from the lower surface of the bases 21 and 31 in a generally rod-shaped manner. It should be noted that the first finger 2 and the second finger 3 may have shapes other than rod-shaped, or they may have different shapes from each other.

[0046] The support 4 movably supports the first finger 2 and the second finger 3 at the lower part of the base 1. The movement direction of the first finger 2 and the second finger 3 is the width direction of the base 1, i.e., the arrangement direction of the two fingers 2 and 3. The first finger 2 and the second finger 3 move while maintaining a constant posture. More specifically, the two fingers 2 and 3 can approach each other in the movement direction to grasp (clamp) the workpiece from the outside. Furthermore, the two fingers 2 and 3 can also separate from each other in the movement direction to grasp the workpiece from the inside.

[0047] The support part 4 has a guide rail 41, a first guide block 42, and a second guide block 43.

[0048] Guide rail 41, used to guide the first guide block 42 and the second guide block 43, is mounted on the lower part of the base 1. Guide rail 41 is a straight rail extending in the width direction of the base 1. More specifically, guide rail 41 is a rail extending in the movement direction of the first finger 2 and the second finger 3. Guide rail 41 is arranged across the approximate width direction of the base 1.

[0049] The first guide block 42 and the second guide block 43 are slidably mounted on the guide rail 41 in the extending direction of the guide rail 41, respectively. The first guide block 42 and the second guide block 43 are formed in a cylindrical shape. The guide rail 41 is located inside the first guide block 42 and the second guide block 43 (see reference). Figure 3 , Figure 4 wait).

[0050] The lower surface of the first guide block 42 becomes the finger mounting portion 425 for mounting the first finger 2. The lower surface of the second guide block 43 becomes the finger mounting portion 435 for mounting the second finger 3. Specifically, each of the two fingers 2 and 3 is mounted on the first guide block 42 and the second guide block 43 by bolting the bases 21 and 31 of each finger 2 and 3 to the finger mounting portions 425 and 435. In this way, the two fingers 2 and 3 are movably supported in the direction of the guide rail 41. In the support portion 4, a range of motion for the two fingers 2 and 3 is set, that is, a predetermined range of motion (hereinafter also referred to as the range of motion of the two fingers 2 and 3).

[0051] Furthermore, the first guide block 42 has a wire mounting portion 421 on its upper part. The wire mounting portion 421 is the portion where the end of the wire 56 of the first moving mechanism 5 (described later) and the end of the second wire 66 of the second moving mechanism 6 are mounted. More specifically, the wire mounting portion 421 has a first slit 422 and a second slit 423. The end of the second wire 66 of the second moving mechanism 6 is fixed to the first slit 422, and the end of the wire 56 of the first moving mechanism 5 is fixed to the second slit 423.

[0052] The second guide block 43 has two wire mounting portions 431 and 432 on its upper part. Like the first guide block 42, the wire mounting portions 431 and 432 are for mounting the ends of the wires 56 of the first moving mechanism 5 and the second wires 66 of the second moving mechanism 6. More specifically, a first slit 433 is provided in the wire mounting portion 431, and a second slit 434 is provided in the wire mounting portion 432. The end of the second wire 66 of the second moving mechanism 6 is fixed to the first slit 433, and the end of the wire 56 of the first moving mechanism 5 is fixed to the second slit 434.

[0053] like Figure 6 As shown, viewed from the direction extending toward the guide rail 41, the wire mounting portion 421 is disposed at the center of the base 1 in the width direction within the first guide block 42. Viewed from the direction extending toward the guide rail 41, the two wire mounting portions 431 and 432 are respectively disposed at the two ends of the base 1 in the width direction within the second guide block 43. Therefore, viewed from the direction extending toward the guide rail 41, the aforementioned four slits 422, 423, 433, and 434 do not interfere with each other.

[0054] The first moving mechanism 5 brings the first finger 2 and the second finger 3 closer together in the moving direction, allowing the first finger 2 and the second finger 3 to grasp the workpiece. Furthermore, the first moving mechanism 5 is configured to enable contour-following gripping via the first finger 2 and the second finger 3. It should be noted that the moving direction is the direction in which the first finger 2 and the second finger 3 move within the hand 100, which is consistent with the width direction of the base 1.

[0055] Specifically, the first moving mechanism 5 has a first fixed pulley 51, a second fixed pulley 52, a first movable pulley 53, and a first metal wire 56. The first moving mechanism 5 is disposed in the lower space separated by the intermediate plate 14 within the internal space of the base 1.

[0056] The first fixed pulley 51 is configured on the side of the first finger 2 in the direction of movement of the first finger 2 and the second finger 3. The second fixed pulley 52 is configured on the side of the second finger 3 in the direction of movement of the first finger 2 and the second finger 3. More specifically, the first fixed pulley 51 and the second fixed pulley 52 are configured such that the two fingers 2 and 3 are located between each other in the direction of movement of the two fingers 2 and 3. The first fixed pulley 51 and the second fixed pulley 52 are disposed in the lower part of the lower space within the base 1.

[0057] like Figure 3 as well as Figure 4 As shown, in this example, the first fixed pulley 51 includes two fixed pulleys 511 and 512. The second fixed pulley 52 includes two fixed pulleys 521 and 522. The two fixed pulleys 511 and 512 are coaxially arranged, specifically, they are rotatably supported by a common shaft 515. The two fixed pulleys 521 and 522 are coaxially arranged, specifically, they are rotatably supported by a common shaft 525.

[0058] The first movable pulley 53 is positioned higher than the first fixed pulley 51 and the second fixed pulley 52. ​​The first movable pulley 53 is located on a vertical axis passing through the center between the first fixed pulley 51 and the second fixed pulley 52. Figure 6 as well as Figure 7 As shown, in this example, the first movable pulley 53 comprises three movable pulleys 531, 532, and 533. These three movable pulleys 531, 532, and 533 are coaxially arranged and, specifically, are rotatably supported by a common shaft 535. It should be noted that movable pulley 531 has two wire grooves, allowing the first wire 56 to be double-wound.

[0059] The first metal wire 56 is an example of a first cord-like component. The first metal wire 56 has two ends (first end 56a and second end 56b), which are sequentially wound around the second fixed pulley 52, the first movable pulley 53, and the first fixed pulley 51 from the first finger 2 toward the second finger 3. These two ends are directly or indirectly connected to each of the first finger 2 and the second finger 3. This merely specifies the winding order among the three pulleys—the second fixed pulley 52, the first movable pulley 53, and the first fixed pulley 51—and does not preclude the possibility of other pulleys being placed between these pulleys while the first metal wire 56 is wound. Furthermore, the first moving mechanism 5 is not limited to the above structure.

[0060] More specifically, in the first moving mechanism 5, [the following was carried out] Figure 9 The wiring of the first metal wire 56 is shown. The first end 56a of the first metal wire 56 is fixed to the wire mounting portion 432 (second slit 434) of the second guide block 43, indirectly connecting to the second finger 3. The second end 56b of the first metal wire 56 is fixed to the wire mounting portion 421 (second slit 423) of the first guide block 42, indirectly connecting to the first finger 2. That is, the first end 56a of the first metal wire 56 is connected to the second finger 3 via the second guide block 43, and the second end 56b of the first metal wire 56 is connected to the first finger 2 via the first guide block 42. Furthermore, the first metal wire 56 is sequentially wound around the fixed pulley 512 (first fixed pulley 51), the movable pulley 533 (first movable pulley 53), the fixed pulley 511 (first fixed pulley 51), the movable pulley 531 (first movable pulley 53), the fixed pulley 522 (second fixed pulley 52), the movable pulley 532 (first movable pulley 53), and the fixed pulley 521 (second fixed pulley 52), starting from the first end 56a side. It should be noted that the first metal wire 56 is doubly wound around the movable pulley 531 (also refer to...). Figure 7 ).

[0061] The second moving mechanism 6 separates the first finger 2 and the second finger 3 in the moving direction, allowing the first finger 2 and the second finger 3 to grasp the workpiece. Furthermore, the second moving mechanism 6 is also configured to enable contour-based grasping via the first finger 2 and the second finger 3. It should be noted that the moving direction is the same as that of the first moving mechanism 5, which is the direction in which the first finger 2 and the second finger 3 move within the hand 100.

[0062] Specifically, the second moving mechanism 6 has a third fixed pulley 61, a fourth fixed pulley 62, a second movable pulley 65, and a second metal wire 66. The second moving mechanism 6 also has a fifth fixed pulley 63 and a sixth fixed pulley 64. Like the first moving mechanism 5, the second moving mechanism 6 is disposed in the lower space within the base 1.

[0063] The third fixed pulley 61 is positioned on the side of the first finger 2 in the direction of movement of the first finger 2 and the second finger 3. The fourth fixed pulley 62 is positioned on the side of the second finger 3 in the direction of movement of the first finger 2 and the second finger 3. That is, the third fixed pulley 61 and the fourth fixed pulley 62 are configured such that the two fingers 2 and 3 are positioned between each other in the direction of movement of the two fingers 2 and 3. The third fixed pulley 61 and the fourth fixed pulley 62 are disposed in the lower part of the lower space within the base 1. In this example, the third fixed pulley 61 and the fourth fixed pulley 62 are each formed as a single fixed pulley.

[0064] The fifth fixed pulley 63 and the sixth fixed pulley 64 are disposed in the upper part of the lower space within the base 1. The fifth fixed pulley 63 is disposed above the third fixed pulley 61. The sixth fixed pulley 64 is disposed above the fourth fixed pulley 62. The fifth fixed pulley 63 and the sixth fixed pulley 64 are disposed at the same height as each other.

[0065] In this example, the fifth fixed pulley 63 comprises three fixed pulleys 631, 632, and 633. The sixth fixed pulley 64 comprises three fixed pulleys 641, 642, and 643. The three fixed pulleys 631, 632, and 633 are coaxially arranged with each other, specifically, they are rotatably supported by a common shaft 635. The three fixed pulleys 641, 642, and 643 are coaxially arranged with each other, specifically, they are rotatably supported by a common shaft 645.

[0066] The second movable pulley 65 is positioned higher than the third fixed pulley 61 and the fourth fixed pulley 62, and lower than the fifth fixed pulley 63 and the sixth fixed pulley 64. The second movable pulley 65 is located on a vertical axis passing through the center between the third fixed pulley 61 and the fourth fixed pulley 62, and the center between the fifth fixed pulley 63 and the sixth fixed pulley 64. Figure 6 as well as Figure 7 As shown, in this example, the second movable pulley 65 comprises three movable pulleys 651, 652, and 653. These three movable pulleys 651, 652, and 653 are coaxially arranged and, specifically, are rotatably supported by a common shaft 535. That is, the first movable pulley 53 of the first moving mechanism 5 and the second movable pulley 65 of the second moving mechanism 6 are coaxially arranged and, specifically, are rotatably supported by a common shaft 535. The first movable pulley 53 and the second movable pulley 65 are configured to move and rotate as a single unit. It should be noted that the movable pulley 653 has two wire grooves, allowing the second wire 66 to be double-wound.

[0067] The second metal wire 66 is an example of a second cord-like component. The second metal wire 66 has two ends (first end 66a and second end 66b), which are sequentially wound around the third fixed pulley 61, the second movable pulley 65, and the fourth fixed pulley 62 from the first finger 2 toward the second finger 3. These two ends are directly or indirectly connected to each of the first finger 2 and the second finger 3. This merely specifies the winding order of the three pulleys (third fixed pulley 61, second movable pulley 65, and fourth fixed pulley 62), and does not preclude the possibility of other pulleys being placed between these pulleys while the second metal wire 66 is wound.

[0068] More specifically, in the second moving mechanism 6, the following is performed: Figure 10The wiring of the second metal wire 66 is shown. The first end 66a of the second metal wire 66 is fixed to the wire mounting portion 421 (first slit 422) of the first guide block 42, indirectly connecting to the first finger 2. The second end 66b of the second metal wire 66 is fixed to the wire mounting portion 431 (first slit 433) of the second guide block 43, indirectly connecting to the second finger 3. That is, the first end 66a of the second metal wire 66 is connected to the first finger 2 via the first guide block 42, and the second end 66b of the second metal wire 66 is connected to the second finger 3 via the second guide block 43. Furthermore, the second metal wire 66, starting from the first end 66a side, is sequentially wound around the third fixed pulley 61, fixed pulley 633 (fifth fixed pulley 63), fixed pulley 643 (sixth fixed pulley 64), movable pulley 652 (second movable pulley 65), fixed pulley 642 (sixth fixed pulley 64), movable pulley 653 (second movable pulley 65), fixed pulley 632 (fifth fixed pulley 63), movable pulley 651 (second movable pulley 65), fixed pulley 631 (fifth fixed pulley 63), fixed pulley 641 (sixth fixed pulley 64), and fourth fixed pulley 62. It should be noted that the second metal wire 66 is double-wound around the movable pulley 653 (also refer to...). Figure 7 ).

[0069] And, as Figure 6 As shown, the first moving mechanism 5 and the second moving mechanism 6 share two common first cylinders 57. The first cylinder 57 is an example of both a first actuator and a second actuator. That is, the first actuator also functions as the second actuator. In other words, the first actuator and the second actuator are the same actuator.

[0070] The first cylinder 57 moves the first movable pulley 53, causing the tension of the first metal wire 56 in the first moving mechanism 5 to act on the first finger 2 and the second finger 3, thereby bringing the first finger 2 and the second finger 3 closer together. Furthermore, the first cylinder 57 moves the second movable pulley 65, causing the tension of the second metal wire 66 in the second moving mechanism 6 to act on the first finger 2 and the second finger 3, thereby separating the first finger 2 and the second finger 3.

[0071] More specifically, the first cylinder 57 can move the first movable pulley 53 and the second movable pulley 65 by moving a common shaft 535. The piston rod 571 of the first cylinder 57 is connected to both ends of the shaft 535 via connecting members 572. The first cylinder 57 is configured such that the piston rod 571 reciprocates (forward and backward) in the vertical direction.

[0072] According to the reciprocating motion (forward and backward movement) of the piston rod 571, the shaft 535, and even the first movable pulley 53 and the second movable pulley 65, move up and down. For example, when the piston rod 571 moves forward, that is, when the piston rod 571 is pushed out and rises, the first movable pulley 53 and the second movable pulley 65 move upward (see reference). Figure 6 (See the diagram with double-dotted lines on the upper side). Furthermore, when the piston rod 571 retracts, that is, when the piston rod 571 is pulled in and descends, the first movable pulley 53 and the second movable pulley 65 move downwards (see...). Figure 6 (The diagram with double-dotted lines shown on the lower side).

[0073] In other words, such as Figure 9 As shown, in the first moving mechanism 5, when the first movable pulley 53 moves upward (refer to the solid arrow), the tension of the first wire 56 acts on the two fingers 2 and 3 via the first guide block 42 and the second guide block 43, resulting in the two fingers 2 and 3 approaching each other (refer to the dashed arrow). Furthermore, as... Figure 10 As shown, in the second moving mechanism 6, when the second movable pulley 65 moves downward (refer to the arrow in the solid line), the tension of the second metal wire 66 acts on the two fingers 2 and 3 through the first guide block 42 and the second guide block 43, resulting in the two fingers 2 and 3 separating from each other (refer to the arrow in the dashed line).

[0074] In this way, the direction of movement of the first movable pulley 53, which is used to bring the first finger 2 and the second finger 3 closer together in the first moving mechanism 5, is opposite to the direction of movement of the second movable pulley 65, which is used to separate the first finger 2 and the second finger 3 from each other in the second moving mechanism 6. Therefore, the first movable pulley 53 and the second movable pulley 65 can be moved using a common first cylinder 57 as described above.

[0075] The first adjustment mechanism 7 moves the first finger 2 and the second finger 3 while maintaining a distance between them by rotating the first movable pulley 53 and moving the first metal wire 56. Furthermore, the first adjustment mechanism 7 moves the first finger 2 and the second finger 3 while maintaining a distance between them by rotating the second movable pulley 65 and moving the second metal wire 66. The first adjustment mechanism 7 also functions as a second adjustment mechanism.

[0076] Specifically, the first adjustment mechanism 7 includes a third movable pulley 71, a third metal wire 72, a guide 73, a metal wire mounting part 76, and a third cylinder 77. Furthermore, the first adjustment mechanism 7 moves the first finger 2 and the second finger 3 so that the center of the interval between the first finger 2 and the second finger 3 is located at the center of the movable range of the first finger 2 and the second finger 3.

[0077] The third movable pulley 71 moves and rotates integrally with the first movable pulley 53 of the first moving mechanism 5 and the second movable pulley 65 of the second moving mechanism 6. Specifically, as Figure 7 As shown, the third movable pulley 7 is coaxially arranged with the first movable pulley 53 and the second movable pulley 65, and is rotatably supported by a common shaft 535. The third movable pulley 71 is located between the first movable pulley 53 and the second movable pulley 65. More specifically, the third movable pulley 71 is integrally formed with the movable pulleys 531 of the first moving mechanism 5 and 653 of the second moving mechanism 6 located on either side of it. Therefore, the movable pulleys 531, 71, and 653 rotate together. That is, as the movable pulleys 531 and 653 rotate due to the contour grip described later, the third movable pulley 71 reliably rotates. The third movable pulley 71 also serves as the fourth movable pulley.

[0078] Furthermore, the first metal wire 56 is fixed to the movable pulley 531 of the first movable pulley 53. Therefore, when the first metal wire 56 moves, the movable pulley 531 rotates. Also, the second metal wire 66 is fixed to the movable pulley 653 of the second movable pulley 65. Therefore, when the second metal wire 66 moves, the movable pulley 653 rotates. Specifically, the fixing part P1 for fixing the first metal wire 56 is provided on the movable pulley 531, and the fixing part P2 for fixing the second metal wire 66 is provided on the movable pulley 653. Therefore, it is possible to prevent the first metal wire 56 and the second metal wire 66 from sliding relative to the movable pulleys 531 and 653 when they move. It should be noted that... Figure 7 For ease of explanation, the positions of the fixing parts P1 and P2 are shown in a simplified manner.

[0079] The third metal wire 72 is connected to the third movable pulley 71 and is wound around the third movable pulley 71 by the rotation of the movable pulleys 531 and 653. The third metal wire 72 is an example of a third cable-like component and also an example of a fourth cable-like component. That is, the third metal wire 72 also serves as a fourth cable-like component. Specifically, the first end 72a of the third metal wire 72 is mounted on the wire mounting portion 76, which is provided in the upper space within the base 1. The second end 72b of the third metal wire 72 is mounted on the third movable pulley 71.

[0080] like Figure 8As shown, the third movable pulley 71 has two sections 711 and 712. The two sections 711 and 712 generally have a shape that divides a flat cylindrical component in two radially. In the third movable pulley 71, the two sections 711 and 712 are arranged with a predetermined gap 713 between them. That is, two gaps 713 are provided between the two sections 711 and 712. The two gaps 713 are positioned 180 degrees apart from each other in the circumferential direction of the third movable pulley 71. The third wire 72 has branches 721 and 722, which are formed by dividing a second end 72b in two, and the ends of these branches 721 and 722 constitute the second end 72b. The two second ends 72b of the third wire 72 are respectively inserted into the two gaps 713. The second ends 72b of the third wire 72 are not dislodged from the gaps 713. In this way, the second ends 72b of the third wire 72 are mounted on the third movable pulley 71. One of the two branches 721 and 722 of the third metal wire 72 is configured to be wound around the outer periphery of the torso 711 as the third movable pulley 71 rotates.

[0081] The guide portion 73 is generally cylindrical and is disposed on the intermediate plate 14. The third metal wire 72 extends from the third movable pulley 71 through the guide portion 73 into the upper space within the base 1. That is, the guide portion 73 guides the third metal wire 72 in the vertical direction. In the upper space within the base 1, a movable pulley 74 is disposed between the guide portion 73 and the wire mounting portion 76. That is, the third metal wire 72, passing through the guide portion 73, is mounted on the wire mounting portion 76 via the movable pulley 74.

[0082] The movable pulley 74 is rotatably mounted on the connecting member 772. Specifically, a shaft 741 is provided in the connecting member 772, and the movable pulley 74 is rotatably supported by the shaft 741. The shaft 741 is arranged to extend in the vertical direction. The connecting member 772 is connected to the piston rod 771 of the third cylinder 77.

[0083] The third cylinder 77 causes the first movable pulley 53 and the second movable pulley 65 to rotate back by pulling back the third metal wire 72 wound around the third movable pulley 71. That is, the third cylinder 77 causes the first movable pulley 53 and the second movable pulley 65 to rotate back in the opposite direction to the direction in which the third metal wire 72 is wound around the third movable pulley 71 by pulling back the third metal wire 72 from the third movable pulley 71.

[0084] The third cylinder 77 is an example of a third actuator, also serving as a fourth actuator. The third cylinder 77 is configured such that the piston rod 771 reciprocates (forward and backward) in the horizontal direction. For example, at the start of the closing gripping action and the opening gripping action described later, the piston rod 771 retracts ( Figure 5(The state is represented by a solid line in the middle). Furthermore, as the piston rod 771 advances, the third metal wire 72 wound around the third movable pulley 71 is pulled out ( Figure 5 (The state is represented by a double-dotted line in the middle).

[0085] Furthermore, the first adjustment mechanism 7 is configured to bring the third movable pulley 71 to a predetermined first rotational position by pulling the third metal wire 72 back to its maximum extent. By bringing the third movable pulley 71 to the first rotational position, the first finger 2 and the second finger 3 are moved to a predetermined first position while maintaining a distance between them. In this example, the position of the third movable pulley 71 when the third metal wire 72 is pulled back to its maximum extent is set as the first rotational position. The predetermined first position is set as the center of the movable range of the two fingers 2 and 3.

[0086] Control device 8 is, for example, a robot controller including a computer such as a microcontroller. Figure 11 As shown, the control device 8 has a storage unit 81, an arithmetic unit 82, and a control unit 83.

[0087] The storage unit 81, such as ROM and RAM, stores the basic program for the robot controller, various fixed data, and other information. The arithmetic unit 82, such as a CPU, reads and executes the basic program and other software stored in the storage unit 81 to generate control instructions for controlling various movements of the robot arm 10 and robot hand 100. The control unit 83 drives and controls the first cylinder 57, the second cylinder 58, and the third cylinder 77 according to the control instructions generated by the arithmetic unit 82.

[0088] (action)

[0089] Reference Figures 12-22 The actions of the hand 100 will be described. The robot hand 100 performs actions such as bringing the first finger 2 and the second finger 3 closer together (closing) to grasp a workpiece (hereinafter referred to as "closing gripping action"), separating the first finger 2 and the second finger 3 from each other (opening) to grasp a workpiece (hereinafter referred to as "opening gripping action"), and moving to the center C of the movable range of the two fingers 2 and 3 while maintaining the distance between them (hereinafter referred to as "centering action"). It should be noted that, for ease of explanation, Figures 12-21 (Apart from Figure 15 as well as Figure 16 The structure of the first moving mechanism 5 and the second moving mechanism 6 is simply shown in the figure.

[0090] At the start of the closing gripping action, the piston rods 571 and 571 of the first cylinders 57 and 57 are in a retracted (descended) state, and the piston rod 771 of the third cylinder 77 is also in a retracted state. During the closing gripping action, the robot arm 10 first moves the hand 100 to the position of the workpiece W to be gripped. The workpiece W is placed in a state where horizontal movement is restricted. The workpiece W is, for example, formed in a cylindrical or prismatic shape. It should be noted that when the hand 100 moves to the position of the workpiece W, since the two fingers 2 and 3 are fully spread, there is no wobbling.

[0091] With hand 100 moved to the position of workpiece W, fingers 2 and 3 are positioned on the outside of workpiece W. For example... Figure 12 As shown, in this state, sometimes the center C of the movable range of the two fingers 2 and 3 (hereinafter, simply referred to as "the center C of the movable range") deviates from the center of the workpiece W. That is, sometimes the center of the interval between the first finger 2 and the second finger 3 (hereinafter, simply referred to as "the center of the two fingers 2 and 3") deviates from the center of the workpiece W. In this example, it is assumed that the center of the workpiece W deviates towards the first finger 2 side for explanation.

[0092] Furthermore, when the closing gripping action begins, the third movable pulley 71 is in the first rotational position. And, as... Figure 13 As shown, the third metal wire 72 is not in a taut state, but in a slack state. At this time, in the first movable pulley 53, for ease of explanation, it is assumed that the fixed part P1 is located at the top of the movable pulley 531. Furthermore, when the closing gripping action begins, the center of the two fingers 2 and 3 is aligned with the center C of the movable range.

[0093] In this state, the first cylinders 57 and 571 are controlled by the control device 8, causing the piston rods 571 and 571 to advance (rise), and the first movable pulley 53 to rise. Thus, as... Figure 14 As shown, due to the tension of the first wire 56 generated by the rise of the first movable pulley 53, the two fingers 2 and 3 move closer to each other. That is, the two fingers 2 and 3 move towards the workpiece W respectively. At this time, since the resistance to the movement of each of the two fingers 2 and 3 is approximately the same, the amount of movement of the two fingers 2 and 3 is approximately equal. Therefore, the first movable pulley 53 rises without rotating. Then, the first finger 2 of the two fingers 2 and 3 contacts the workpiece W first and stops. At this time, the forward movement of the piston rods 571 in the first cylinders 57 continues.

[0094] like Figure 15As shown, even if the first finger 2 contacts the workpiece W and stops, the first movable pulley 53 continues to rise. Therefore, the second finger 3 continues to move smoothly without stopping. When the resistance to the movement of the first finger 2 increases due to its contact with the workpiece W, the first wire 56 in the first movable pulley 53 moves from the side of the first fixed pulley 51 to the side of the second fixed pulley 52 as the first movable pulley 53 rises. This movement of the first wire 56 causes the movable pulley 531 to rotate. That is, the movable pulley 531 (first movable pulley 53) rotates while rising. Here, since the first wire 56 is fixed to the movable pulley 531, the movable pulley 531 reliably rotates as the first wire 56 moves. Therefore, the tension of the first wire 56 only acts on the side of the second finger 3, where the resistance to movement is smaller, and only the second finger 3 continues to move towards the workpiece W (first finger 2). Then, the second finger 3 contacts the workpiece W and stops.

[0095] In the first adjustment mechanism 7, the third movable pulley 71 also rotates in the same direction as the aforementioned movable pulley 531. Figure 16 As shown, when the third movable pulley 71 rotates, the third metal wire 72 is wound around the third movable pulley 71. More specifically, one of the two slack branches 721 and 722 in the third metal wire 72 is wound around the main body 711. That is, the slack portion of the third metal wire 72 is wound around the third movable pulley 71. Therefore, for example, compared to the state when the piston rod 771 of the third cylinder 77 is advanced, tightening the third metal wire 72, the resistance when the third movable pulley 71 rotates is reduced. It should be noted that at this time, the piston rod 771 of the third cylinder 77 remains retracted.

[0096] In this way, the workpiece W is grasped using the first finger 2 and the second finger 3, completing the closed gripping action. That is, the workpiece W is grasped from the outside using two fingers 2 and 3. Thus, even when the center of the workpiece W deviates from the center C of its movable range when the hand 100 moves to the position of the workpiece W, the contouring grip can still be performed smoothly. Moreover, since the rotational resistance of the third movable pulley 71 when the third wire 72 is wound is reduced, as described above, the contouring grip can be performed even more smoothly. After the closed gripping action is completed, the robot arm 10 moves the hand 100 upward, and the grasped workpiece W moves upward from its loading position.

[0097] Next, perform the calming action. While being held in a shape-mimicking grip as described above, such as... Figure 15 As shown, since the center of the two fingers 2 and 3 is deviated from the center C of the movable range, a centering action is performed.

[0098] During the centering action, the third cylinder 77, controlled by the control device 8, moves the retracting piston rod 771 forward. When the piston rod 771 moves forward, as... Figure 17 As shown, the third metal wire 72 is pulled back from the third movable pulley 71, and the third metal wire 72, including the two branches 721 and 722, becomes taut. That is, the third metal wire 72 is pulled back to the maximum extent from the third movable pulley 71, and the third movable pulley 71 returns to its first rotational position. In this way, since the third metal wire 72 can no longer be pulled back, the forward movement of the piston rod 771 of the third cylinder 77 stops.

[0099] When the third movable pulley 71 rotates like this, Figure 18 As shown, the movable pulley 531 (first movable pulley 53) is oriented in the same direction as the rotation during the closing gripping action. Figure 15 The rotation direction is opposite to the direction shown. That is, the movable pulley 531 rotates in the opposite direction, and the fixed part P1 returns to the uppermost rotational position (the position before the rotation via the "closing grip action"). In this way, the first metal wire 56 moves, and the first finger 2 and the second finger 3 move to the center C of the movable range while maintaining the distance between them. That is, the first finger 2 and the second finger 3 move while holding the workpiece W, and the center of the two fingers 2 and 3 coincides with the center C of the movable range. In this way, the centering action is completed. In this way, the first finger 2 and the second finger 3 can be moved to the center C of the movable range without detecting the position of the first finger 2 and the second finger 3 by sensors or the like. It should be noted that in this example, the centering action of moving the two fingers 2 and 3 to the center C of the movable range is described, but the hand 100 can move the two fingers 2 and 3 to any position in the direction of movement and fix them.

[0100] Next, the opening and gripping action will be explained. At the start of the opening and gripping action, the piston rods 571 of the first cylinders 57 are in the forward (rising) state, and the piston rod 771 of the third cylinder 77 is in the retracted state. During the opening and gripping action, firstly, the robot arm 10l moves the hand 100 to the position of the workpiece W to be gripped. The workpiece W is placed in a state where horizontal movement is restricted. The workpiece W is, for example, a cylindrical component with an internal circular or rectangular shape.

[0101] With hand 100 moved to the position of workpiece W, fingers 2 and 3 are located inside workpiece W. For example... Figure 19As shown, in this state, sometimes the center C of the movable range of the two fingers 2 and 3 deviates from the center of the workpiece W. That is, sometimes the center of the gap between the first finger 2 and the second finger 3 deviates from the center of the workpiece W. In this example, it is assumed that the center of the workpiece W deviates towards the second finger 3. Furthermore, the opening and gripping action also begins when the center of the gap between the first finger 2 and the second finger 3 is aligned with the center C of the movable range of the two fingers 2 and 3.

[0102] Furthermore, at the start of the opening grip action, the third movable pulley 71 is in the first rotational position. Also, as at the start of the closing grip action, the third metal wire 72 is not in a taut state, but rather in a slack state (see reference). Figure 13 At this time, for ease of explanation, it is assumed that the fixed part P2 is located at the bottom of the movable pulley 653 in the second movable pulley 65. Furthermore, at the start of the opening and gripping action, the centers of the two fingers 2 and 3 are aligned with the center C of the movable range.

[0103] In this state, the first cylinders 57 and 571 are controlled by the control device 8, and the piston rods 571 and 571 retract (descend), causing the second movable pulley 65 to descend. Thus, as... Figure 20 As shown, due to the tension of the second wire 66 generated by the descent of the second movable pulley 65, the two fingers 2 and 3 move separately from each other. That is, the two fingers 2 and 3 move towards the workpiece W respectively. At this time, since the resistance to the movement of each of the two fingers 2 and 3 is approximately the same, the amount of movement of the two fingers 2 and 3 is approximately equal. Therefore, the second movable pulley 65 descends without rotating. Then, the first finger 2 of the two fingers 2 and 3 contacts the workpiece W first and stops. At this time, the retracting action of the piston rods 571 in the first cylinders 57 continues.

[0104] like Figure 21As shown, even if the first finger 2 contacts the workpiece W and stops, the second movable pulley 65 continues its descent. Therefore, the second finger 3 continues to move smoothly without stopping. When the resistance to the movement of the first finger 2 increases due to its contact with the workpiece W, the second wire 66 moves from the fifth fixed pulley 63 (third fixed pulley 61) to the sixth fixed pulley 64 (fourth fixed pulley 62) as the second movable pulley 65 descends. The movable pulley 653 rotates due to the movement of the second wire 66. That is, the movable pulley 653 (second movable pulley 65) rotates while descending. Here, since the second wire 66 is fixed to the movable pulley 653, the movable pulley 653 reliably rotates with the movement of the second wire 66. Therefore, the tension of the second wire 66 acts only on the second finger 3, which experiences less resistance to movement, and only the second finger 3 continues to move towards the workpiece W. Then, the second finger 3 contacts the workpiece W and stops.

[0105] Even at this time, in the first adjustment mechanism 7, the third movable pulley 71 also rotates in the same direction as the aforementioned movable pulley 653 as the latter rotates. For example... Figure 16 As shown, when the third movable pulley 71 rotates, the third metal wire 72 wraps around it. That is, similar to the closing gripping action, one of the two loose branches 721 and 722 of the third metal wire 72 wraps around the torso 711. Therefore, the resistance to rotation of the third movable pulley 71 is reduced. It should be noted that at this time, the piston rod 771 of the third cylinder 77 remains retracted.

[0106] In this way, the workpiece W is grasped using the first finger 2 and the second finger 3 to complete the opening gripping action. That is, the workpiece W is grasped from the inside using two fingers 2 and 3. In this way, even if the center of the workpiece W deviates from the center C of the movable range when the hand 100 moves to the position of the workpiece W, the contour gripping can still be performed smoothly. Furthermore, since the rotational resistance of the third movable pulley 71 when the third metal wire 72 is wound is reduced as described above, the contour gripping can be performed more smoothly. After the opening gripping action is completed, the robot arm 100 moves the hand 100 upward, and the grasped workpiece W is moved upward from the place where it was placed.

[0107] Next, perform the calming action. While maintaining the shape-mimicking grip as described above, such as... Figure 21 As shown, since the center of the two fingers 2 and 3 is deviated from the center C of the movable range, a centering action is performed.

[0108] During the centering action, the third cylinder 77, controlled by the control device 8, moves the retracting piston rod 771 forward. When the piston rod 771 moves forward, as... Figure 17As shown, the third metal wire 72 is pulled back from the third movable pulley 71, and the third metal wire 72, including the two branches 721 and 722, becomes taut. That is, the third metal wire 72 is pulled back to its maximum extent from the third movable pulley 71, and the third movable pulley 71 returns to its first rotational position. In this way, since the third metal wire 72 cannot be pulled back, the forward movement of the piston rod 771 of the third cylinder 77 stops.

[0109] When the third movable pulley 71 rotates like this, Figure 22 As shown, the movable pulley 653 (the second movable pulley 65) is oriented in the same direction as the rotation of the "opening and gripping action" ( Figure 21 The rotation direction is opposite to the direction shown. That is, the movable pulley 653 rotates in the opposite direction, and the fixed part P2 returns to the lowest rotational position (the position before rotation via the "opening grip action"). This causes the second wire 66 to move, and the first finger 2 and the second finger 3 move to the center C of the movable range while maintaining a distance between them. In other words, the first finger 2 and the second finger 3 move while holding the workpiece W, and the centers of the two fingers 2 and 3 are aligned with the center C of the movable range. Thus, the centering action is completed. In this way, the first finger 2 and the second finger 3 can be moved to the center C of the movable range without detecting their positions using sensors or the like.

[0110] As described above, the robotic hand 100 includes a first finger 2, a second finger 3, and a first moving mechanism 5. The first moving mechanism 5 brings the first finger 2 and the second finger 3 closer together in a predetermined moving direction, allowing the first finger 2 and the second finger 3 to grasp the workpiece W. The first moving mechanism 5 has a first movable pulley 53, a first metal wire 56 (a first cable-like component), and a first cylinder 57 (a first actuator). The first metal wire 56 (the first cable-like component) has two ends (a first end 56a and a second end 56b) that are wound around the first movable pulley 53. These two ends are connected to each of the first finger 2 and the second finger 3. The first cylinder 57 (the first actuator) moves the first movable pulley 53. Furthermore, the first cylinder 57 moves the first movable pulley 53 so that the tension of the first metal wire 56 acts on the first finger 2 and the second finger 3, bringing the first finger 2 and the second finger 3 closer together.

[0111] More specifically, the first moving mechanism 5 has a first fixed pulley 51 disposed on the side of the first finger 2 and a second fixed pulley 52 disposed on the side of the second finger 3 in the moving direction. The first metal wire 56 is wound sequentially from the first finger 2 toward the second finger 3 around the second fixed pulley 52, the first movable pulley 53 and the first fixed pulley 51.

[0112] According to the structure, corresponding to the amount of movement of the first movable pulley 53 caused by the first cylinder 57, the first finger 2 and the second finger 3 are respectively pulled and moved by the first metal wire 56. Here, the portion of the first metal wire 56 extending from the first movable pulley 53 to the first fixed pulley 51 is wrapped around the first fixed pulley 51 and connected to the second finger 3. On the other hand, the portion of the first metal wire 56 extending from the first movable pulley 53 to the second fixed pulley 52 is wrapped around the second fixed pulley 52 and connected to the first finger 2. The first fixed pulley 51 is arranged on the side of the first finger 2 in the direction of movement, while the second fixed pulley 52 is arranged on the side of the second finger 3 in the direction of movement. Therefore, when the first finger 2 and the second finger 3 are respectively pulled by the first metal wire 56, the first finger 2 and the second finger 3 move in a direction closer to each other. As a result, the first finger 2 and the second finger 3 approach each other and grasp the workpiece W from the outside.

[0113] At this time, the movement amounts of the first finger 2 and the second finger 3, corresponding to the movement amount of the first movable pulley 53, are appropriately adjusted based on the resistance to the movement of the first finger 2 and the resistance to the movement of the second finger 3. For example, when the first finger 2 contacts the workpiece W, and the resistance to the movement of the first finger 2 increases, for example, the first finger 2 stops, and the movement amount of the second finger 3 increases appropriately. Therefore, the second finger 3 can continue to move smoothly toward the workpiece W. As a result, the workpiece W can be reached through the second finger 3, and a contour grip can be performed smoothly.

[0114] Furthermore, for example, since contour gripping can be performed smoothly even when the center C of the movable range deviates from the center of the workpiece W, as described above, it is not necessary to perform high-precision position detection of the workpiece W when moving the robot hand 100 to the position of the workpiece W. Therefore, the control load can be reduced.

[0115] Furthermore, the robotic hand 100 also includes a second moving mechanism 6, which separates the first finger 2 and the second finger 3 from each other in the direction of movement, allowing the first finger 2 and the second finger 3 to grasp the workpiece W. The second moving mechanism 6 includes a second movable pulley, a second metal wire 66 (a second cable-like component), and a first cylinder 57 (a second actuator). The second metal wire 66 (the second cable-like component) has two ends (a first end 66a and a second end 66b) that are wound around the second movable pulley 65. These two ends (a first end 66a and a second end 66b) are connected to each of the first finger 2 and the second finger 3. The first cylinder 57 (the second actuator) moves the second movable pulley 65. The movement of the second movable pulley 65 causes the tension of the second metal wire 66 to act on the first finger 2 and the second finger 3, separating them from each other.

[0116] More specifically, the second moving mechanism 6 has a third fixed pulley 61 disposed on the side of the first finger 2 and a fourth fixed pulley 62 disposed on the side of the second finger 3 in the direction of movement. The second metal wire 66 is wound sequentially from the first finger 2 toward the second finger 3 around the third fixed pulley 61, the second movable pulley 65 and the fourth fixed pulley 62.

[0117] According to the structure, corresponding to the amount of movement of the second movable pulley 65 caused by the first cylinder 57, the first finger 2 and the second finger 3 are respectively pulled and moved by the second wire 66. Here, the portion of the second wire 66 extending from the second movable pulley 65 to the third fixed pulley 61 is wrapped around the third fixed pulley 61 and connected to the first finger 2. On the other hand, the portion of the second wire 66 extending from the second movable pulley 65 to the fourth fixed pulley 62 is wrapped around the fourth fixed pulley 62 and connected to the second finger 3. The third fixed pulley 61 is positioned on the side of the first finger 2 in the direction of movement, while the fourth fixed pulley 62 is positioned on the side of the second finger 3 in the direction of movement. Therefore, when the first finger 2 and the second finger 3 are respectively pulled by the second wire 66, the first finger 2 and the second finger 3 move in a direction of separation from each other. As a result, the first finger 2 and the second finger 3 separate from each other and grasp the workpiece W from the inside.

[0118] At this time, the movement amounts of the first finger 2 and the second finger 3, corresponding to the movement amount of the second movable pulley 62, are appropriately adjusted based on the resistance to the movement of the first finger 2 and the resistance to the movement of the second finger 3. For example, when the first finger 2 contacts the workpiece W, and the resistance to the movement of the first finger 2 increases, for example, the first finger 2 stops, and the movement amount of the second finger 3 increases appropriately. Therefore, the second finger 3 can continue to move smoothly toward the workpiece W. As a result, the workpiece W can be reached through the second finger 3, and a contour grip can be performed smoothly.

[0119] Furthermore, in the robotic hand 100, the first movable pulley 53 and the second movable pulley 65 are configured to move as a single unit. The direction of movement of the first movable pulley 53, which is used to bring the first finger 2 and the second finger 3 closer together, and the direction of movement of the second movable pulley 65, which is used to separate the first finger 2 and the second finger 3, are opposite to each other. Moreover, the first cylinder 57 (first actuator) also functions as the second actuator, causing the first movable pulley 53 and the second movable pulley 65 to move.

[0120] According to the structure described above, the first cylinder 57, which moves the first movable pulley 53, also functions as the second actuator, which moves the second movable pulley 65. Therefore, it is possible to simultaneously perform two actions: bringing the first finger 2 and the second finger 3 closer together to grasp the workpiece W from the outside (closing grip action) and separating the first finger 2 and the second finger 3 to grasp the workpiece W from the inside (opening grip action).

[0121] Furthermore, the robotic hand 100 also includes a first adjustment mechanism 7. This first adjustment mechanism 7 rotates a first movable pulley 53, causing a first metal wire 56 to move, thereby allowing the first finger 2 and the second finger 3 to move while maintaining a distance between them. The first movable pulley 53 and the second movable pulley 65 are configured to rotate as a single unit. The first adjustment mechanism 7 also rotates the second movable pulley 65 together with the first movable pulley 53, causing the first metal wire 56 and the second metal wire 66 to move, thereby allowing the first finger 2 and the second finger 3 to move while maintaining a distance between them.

[0122] According to the structure described above, for example, the first finger 2 and the second finger 3 can be easily moved to any position within the hand 100 while holding the workpiece W. Therefore, for example, the first finger 2 and the second finger 3 can be moved within the hand 100 considering the nature of the next operation. In conventional differential gear mechanisms, due to the effects of gear idling and wobbling, the gripping force may decrease when the gear is rotated in the opposite direction to the gripping direction, making it difficult to move the first finger 2 and the second finger while holding the workpiece.

[0123] Furthermore, in the robotic hand 100, the first adjustment mechanism 7 includes a third movable pulley 71, a third wire 72 (a third cable-like component), and a third cylinder 77 (a third actuator). The third movable pulley 71 moves and rotates integrally with the first movable pulley 53 and the second movable pulley 65. The third wire 72 is connected to the third movable pulley 71 and is wound around the third movable pulley 71 by the rotation of the first movable pulley 53 and the second movable pulley 65. The third cylinder 77 rotates the first movable pulley 53 and the second movable pulley 65 by pulling back the third wire 72 wound around the third movable pulley 71.

[0124] According to the structure described, since the third movable pulley 71 moves and rotates as a unit with the first movable pulley 53 and the second movable pulley 65, a simple structure such as pulling back the third metal wire 72 can be used to rotate the first movable pulley 53 and the second movable pulley 65. This allows for the miniaturization of the robot hand 100.

[0125] Furthermore, in the robotic hand 100, the first metal wire 56 is fixed to the first movable pulley 53, and the second metal wire 66 is fixed to the second movable pulley 65.

[0126] According to the structure, the first metal wire 56 moves reliably with the rotation of the first movable pulley 53 without slipping, and the second metal wire 66 moves reliably with the rotation of the second movable pulley 65 without slipping. Therefore, it is possible to move with high precision while maintaining a distance between the first finger 2 and the second finger 3.

[0127] Furthermore, in the robotic hand 100, the first adjustment mechanism 7 is configured to bring the third movable pulley 71 to a predetermined first rotational position by pulling back the third metal wire 72 to the maximum extent, and by bringing the third movable pulley 71 to the first rotational position, the first finger 2 and the second finger 3 are moved to a predetermined first position while maintaining the distance between them.

[0128] According to the structure, by pulling the third metal wire 72 back to its maximum extent, the third movable pulley 71 is positioned in a first rotational position, thereby allowing the first finger 2 and the second finger 3 to move to a predetermined first position while maintaining a distance between them. Here, by setting the center C of the movable range of the two fingers 2 and 3 as the predetermined first position, the first finger 2 and the second finger 3 can be smoothly and easily centered without detecting the amount of pullback of the third metal wire 72 using sensors or the like.

[0129] Furthermore, the robotic arm 100 uses cylinders 57, 58, and 77 as the first actuator, the second actuator, and the third actuator, respectively.

[0130] According to the aforementioned structure, for example, the robot hand 100 can be constructed at a lower cost compared to using a motor (servo motor). In particular, because the structure moves the first movable pulley 53 and the second movable pulley 65 up and down, the cylinder that performs reciprocating motion is effective.

[0131] (Other implementation methods)

[0132] As described above, the embodiments have been presented as examples of the technology disclosed in this application. However, the technology disclosed herein is not limited to this and can be applied to embodiments with appropriate modifications, substitutions, additions, omissions, etc. Furthermore, the various constituent elements described in the embodiments can be combined to form new embodiments. Moreover, the constituent elements described in the drawings and detailed descriptions include not only those necessary to solve the problem, but also, for the purpose of illustrating the technology, constituent elements that are not necessary to solve the problem. Therefore, one should not immediately assume that those non-essential constituent elements are essential simply because they are described in the drawings and detailed descriptions.

[0133] In the described embodiment, the second moving mechanism 6 may also be omitted. That is, the robot hand 100 may only perform a "closing gripping action" as a gripping action.

[0134] Furthermore, in the described embodiment, the first moving mechanism 5 can be omitted. That is, the robot hand 100 can also simply perform an "opening and gripping action" as a gripping action. In this case, a second adjusting mechanism is provided to replace the first adjusting mechanism 7. The second adjusting mechanism 7 moves the first finger 2 and the second finger 3 while maintaining a distance between them by rotating the second movable pulley 65 and moving the second wire 66 (the second cable-like component).

[0135] Furthermore, when the first moving mechanism 5 is omitted and only the "opening and grasping action" is performed, the second moving mechanism 6 can also be... Figure 23 The structure is as shown. That is, in the second metal wire 66, the first end 66a is connected to the first finger 2, and the second end 66b is connected to the second finger 3. Furthermore, the second metal wire 66 is wound sequentially from the first finger 2 towards the second finger 3 around the third fixed pulley 61, the second movable pulley 65, and the fourth fixed pulley 64. In this second moving mechanism 6, the second movable pulley 65 rises, causing the tension of the second metal wire 66 to act on the first finger 2 and the second finger 3, separating the first finger 2 and the second finger 3 from each other.

[0136] Furthermore, the second adjustment mechanism may also have a fourth movable pulley, a fourth metal wire (fourth cable-like component), and a fourth cylinder (fourth actuator). The fourth movable pulley moves and rotates integrally with the second movable pulley 65. The fourth metal wire (fourth cable-like component) is wound around the fourth movable pulley by the rotation of the second movable pulley 65. The fourth cylinder (fourth actuator) rotates the second movable pulley 65 by pulling back the fourth metal wire wound around the fourth movable pulley.

[0137] Alternatively, the second adjustment mechanism can be configured to pull back the fourth metal wire to the maximum extent so that the fourth movable pulley is in a predetermined second rotational position. By placing the fourth movable pulley in the second rotational position, the first finger 2 and the third finger 3 can be moved to the predetermined second position while maintaining the distance between them.

[0138] Furthermore, in the first adjustment mechanism 7, when the closing gripping action and the opening gripping action begin, the piston rod 771 of the third cylinder 77 is retracted to make the third metal wire 72 slack. In the technology of the present invention, instead of this, the piston rod 771 of the third cylinder 77 is advanced to make the third metal wire 72 taut.

[0139] Furthermore, in the above embodiments, the first adjustment mechanism 7, the second moving mechanism 6 and the first adjustment mechanism 7 can be omitted, or the first moving mechanism 5 and the first adjustment mechanism 7 can be omitted.

[0140] Furthermore, the wiring structure of each of the first metal wire 56 and the second metal wire 66 is not limited to the structure described in the embodiment. That is, any wiring structure is acceptable as long as it allows the tension of the first metal wire 56 and the second metal wire 66 to act on the first finger 2 and the second finger 3 by moving the first movable pulley 53 and the second movable pulley 65 up and down.

[0141] Furthermore, in the described embodiment, the number of fixed pulleys constituting each of the first fixed pulley 51, the second fixed pulley 52, the third fixed pulley 61, the fourth fixed pulley 62, the fifth fixed pulley 63, and the sixth fixed pulley 64, and the number of movable pulleys constituting each of the first movable pulley 53 and the second movable pulley 65, are not limited to the numbers described above. Basically, since the more fixed and movable pulleys there are, the more turns are made, thus suppressing the amount of movement of the first movable pulley 53 and the second movable pulley 65 required to move the first finger 2 and the second finger 3, miniaturization of the hand 100 can be achieved.

[0142] Furthermore, in the described embodiment, the third movable pulley and the third metal wire can also be configured as follows. For example... Figure 24 as well as Figure 25As shown, the third movable pulley 78 has a circular body 781. The second end 79b of the third metal wire 79 is connected to a predetermined position on the outer circumferential surface of the body 781. In the previous embodiment, the third metal wire 72 and the third movable pulley 71 are connected at two points, while in this modified example, the third movable pulley 78 and the third metal wire 79 are connected at one point. After passing through the guide pulley 75, the third metal wire 79 is fixed to the wire mounting portion 76 via the movable pulley 74 connected to the third cylinder 77, as in the previous embodiment (not shown). At this time, when performing a contour gripping action through "closing gripping action" and "opening gripping action", the third movable pulley 78 also rotates along with the rotation of the first movable pulley 53 and the second movable pulley 65. Figure 24 (State). In this way, the third metal wire 79 is wrapped around the body 781 of the third movable pulley 78. Furthermore, during the "centering action," the third metal wire 79 is pulled back to its maximum extent via the third cylinder 77. Figure 25 (The state). That is, in the third movable pulley 78, the connection point of the third metal wire 79 is located at the uppermost position. Therefore, the third movable pulley 78 returns to the first rotational position, and the first movable pulley 53 and the second movable pulley 65 rotate accordingly. As a result, as in the described embodiment, the first finger 2 and the second finger 3 are centered.

[0143] Furthermore, in the described embodiment, components other than the cylinder can also be used as the first actuator, the second actuator, and the third actuator. For example, a motor or a hydraulic cylinder can be cited.

[0144] Furthermore, in the described embodiment, metal wire is used as a cord-like component, but it is not limited to this; for example, a rope made of fiber can also be used.

[0145] Furthermore, in the described embodiment, since the length of the metal wire wound around the first movable pulley 53 and the second movable pulley 65 varies depending on their vertical positions, a certain degree of slack in the wiring is sometimes required. In such cases, since the metal wire may detach from the fixed pulley or the like, for example, a tensioner capable of absorbing excessive slack may be provided, or a guide to prevent the metal wire from detaching may be provided.

Claims

1. A robotic hand, characterized in that: The robotic hand includes a first finger, a second finger, and a first moving mechanism. The first moving mechanism brings the first finger and the second finger closer to each other in a predetermined direction of movement, enabling the first finger and the second finger to grasp a workpiece. The first moving mechanism has a first movable pulley, a first cable-like component, and a first actuator. The first cable-like component has two ends and is wound around the first movable pulley. These two ends are connected to each of the first finger and the second finger. The first actuator causes the first movable pulley to move. The first actuator moves the first movable pulley so that the tension of the first cord-like component acts on the first finger and the second finger, bringing the first finger and the second finger closer together. The robotic hand also includes a first adjustment mechanism, which moves the first finger and the second finger while maintaining a distance between them by rotating the first movable pulley and moving the first cord-like component.

2. The robotic hand according to claim 1, characterized in that: The first moving mechanism has a first fixed pulley disposed on the side of the first finger in the moving direction and a second fixed pulley disposed on the side of the second finger. The first cord-like component is wound sequentially around the second fixed pulley, the first movable pulley, and the first fixed pulley from the first finger toward the second finger.

3. The robotic hand according to claim 1, characterized in that: The first adjustment mechanism has a third movable pulley, a third cable-like component, and a third actuator. The third movable pulley moves and rotates integrally with the first movable pulley. The third cable-like component is connected to the third movable pulley and is wound around the third movable pulley by the rotation of the first movable pulley. The third actuator rotates the first movable pulley by pulling back the third cable-like component wound around the third movable pulley.

4. The robotic hand according to claim 1 or 3, characterized in that: The first cable-like component is fixed to the first movable pulley.

5. The robotic hand according to claim 3, characterized in that: The first cable-like component is fixed to the first movable pulley. The first adjustment mechanism is configured to bring the third movable pulley to a predetermined first rotational position by pulling back the third cable-like component to the maximum extent, and to move the first finger and the second finger to a predetermined first position while maintaining a distance between them by bringing the third movable pulley to the first rotational position.

6. The robotic hand according to claim 1 or 2, characterized in that: The robotic hand also includes a second moving mechanism that separates the first and second fingers from each other in the direction of movement, allowing the first and second fingers to grasp the workpiece. The second moving mechanism includes a third fixed pulley disposed on the side of the first finger and a fourth fixed pulley disposed on the side of the second finger, a second movable pulley, a second cable-like component, and a second actuator. The second cable-like component has two ends that are wound around the third fixed pulley, the fourth fixed pulley, and the second movable pulley. These two ends are connected to each of the first finger and the second finger. The second actuator causes the second movable pulley to move. The second cord-like component wraps sequentially around the third fixed pulley, the second movable pulley, and the fourth fixed pulley from the first finger toward the second finger. The second actuator separates the first and second fingers from each other by moving the second movable pulley to apply tension to the first and second fingers using the second cord-like component.

7. The robotic hand according to claim 6, characterized in that: The first movable pulley and the second movable pulley are configured to move as a single unit. The direction of movement of the first movable pulley used to bring the first and second fingers closer together is opposite to the direction of movement of the second movable pulley used to separate the first and second fingers from each other. The first actuator also functions as the second actuator, causing the first movable pulley and the second movable pulley to move.

8. The robotic hand according to claim 7, characterized in that: The robotic hand also includes a first adjustment mechanism, which moves the first cord-like component by rotating the first movable pulley, thereby allowing the first finger and the second finger to move while maintaining a distance between them. The first movable pulley and the second movable pulley are configured to rotate as a single unit. The first adjustment mechanism moves the first finger and the second finger while maintaining a distance between them by rotating the second movable pulley together with the first movable pulley, thereby moving the first cord-like component and the second cord-like component.

9. The robotic hand according to claim 8, characterized in that: The first adjustment mechanism has a third movable pulley, a third cable-like component, and a third actuator. The third movable pulley moves and rotates integrally with the first movable pulley and the second movable pulley. The third cable-like component is connected to the third movable pulley and is wound around the third movable pulley by the rotation of the first movable pulley and the second movable pulley. The third actuator rotates the first movable pulley and the second movable pulley by pulling back the third cable-like component wound around the third movable pulley.

10. The robotic hand according to claim 8, characterized in that: The first cable-like component is fixed to the first movable pulley. The second cable-like component is fixed to the second movable pulley.

11. The robotic hand according to claim 9, characterized in that: The first cable-like component is fixed to the first movable pulley. The second cable-like component is fixed to the second movable pulley. The first adjustment mechanism is configured to bring the third movable pulley to a predetermined first rotational position by pulling back the third cable-like component to the maximum extent, and to move the first finger and the second finger to a predetermined first position while maintaining a distance between them by bringing the third movable pulley to the first rotational position.

12. A robotic hand, characterized in that: The robotic hand includes a first finger, a second finger, and a second moving mechanism. The second moving mechanism separates the first and second fingers in a predetermined direction of movement, allowing the first and second fingers to grasp a workpiece. The second moving mechanism has a second movable pulley, a second cable-like component, and a second actuator. The second cable-like component has two ends and is wound around the second movable pulley. These two ends are connected to each of the first and second fingers. The second actuator causes the second movable pulley to move. The second actuator moves the second movable pulley, causing the tension of the second cord-like component to act on the first and second fingers, separating the first and second fingers from each other. The robotic hand also includes a second adjustment mechanism, which moves the first finger and the second finger while maintaining a distance between them by rotating the second movable pulley to move the second cable-like component.

13. The robotic hand according to claim 12, characterized in that: The second moving mechanism has a third fixed pulley disposed on the side of the first finger in the moving direction and a fourth fixed pulley disposed on the side of the second finger. The second cord-like component is wound sequentially around the third fixed pulley, the second movable pulley, and the fourth fixed pulley from the first finger toward the second finger.

14. The robotic hand according to claim 12, characterized in that: The second adjustment mechanism has a fourth movable pulley, a fourth cable-like component, and a fourth actuator. The fourth movable pulley moves and rotates integrally with the second movable pulley. The fourth cable-like component is connected to the fourth movable pulley and is wound around the fourth movable pulley by the rotation of the second movable pulley. The fourth actuator rotates the second movable pulley by pulling back the fourth cable-like component wound around the fourth movable pulley.

15. The robotic hand according to claim 12 or 14, characterized in that: The second cable-like component is fixed to the second movable pulley.

16. The robotic hand according to claim 14, characterized in that: The second cable-like component is fixed to the second movable pulley. The second adjustment mechanism is configured to pull back the fourth cable-like component to the maximum extent, so that the fourth movable pulley is in a predetermined second rotational position. By placing the fourth movable pulley in the second rotational position, the first finger and the second finger are moved to a predetermined second position while maintaining a distance between them.

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