JP2018199171A - Gripping device - Google Patents

Abstract

To enable various gripping objects to be gripped using a small number of movable fingers.SOLUTION: A gripping device comprises: a movable finger 3 eccentrically and rotatably attached to a rotary shaft 13 disposed in a base part 2; a first fixed finger 5 and a second fixed finger 6 fixed to the base part, and arranged at positions that allow respective gripping objects to be gripped respectively between each of them and the movable finger when the movable finger is rotated in a predetermined direction with respect to the rotary shaft; and a drive part for rotating the movable finger at least to the predetermined direction. Due to: a difference in respective shapes of parts of the first and the second fixed fingers facing respectively the movable finger at respective closest positions; a difference in respective positional relationships respectively between the first and the second fixed fingers and the rotary shaft; and/or a difference in respective shapes of parts of the movable finger facing respectively the first and the second fixed fingers at the respective closest positions; an object to be gripped that can be gripped between the first fixed finger and the movable finger, and an object to be gripped that can be gripped between the second fixed finger and the movable finger are configured to be different.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a gripping device that grips a gripping object.

  Conventionally, a gripping device that grips a gripping object may be attached to the tip of a robot arm or the tip of a manipulator. As this type of gripping device, for example, a device that grips a gripping object with three gripping fingers as described in Patent Document 1 has been proposed. In the gripping device described in Patent Document 1, three rotating shafts are provided around the central axis set in the device at intervals of 120 °, and the gripping fingers attached with their tips eccentric to the rotating shaft are respectively attached. Three of them are rotated simultaneously with the rotating shaft. By rotating the three gripping fingers toward the extension line of the central axis by the rotation, it is possible to grip a gripping object placed on the extension line of the central axis.

JP 2009-218771 A

  However, since the gripping device described in Patent Document 1 requires three gripping fingers (that is, movable fingers), the manufacturing cost cannot be reduced sufficiently. Further, in the gripping device described in Patent Document 1, since a gripping finger having the same configuration is gripped from three directions of the gripping target, the cylindrical gripping target arranged coaxially with the center axis is used. Only objects can be gripped. In view of this, an object of one aspect of the present disclosure is to provide a technique capable of gripping various gripping objects using a small number of movable fingers.

  The gripping device as one aspect of the present disclosure includes a base (2,102), a movable finger (3, 23, 63, 83, 93, 103), a first fixed finger (5, 105), and a second Fixed fingers (6, 106) and a drive unit (8, 48).

  The movable finger is rotatably provided in an eccentric state with respect to the rotation shaft (13, 113) set at the base. The first fixed finger and the second fixed finger are arranged at a position to hold a gripping object between the movable finger and the movable finger when the movable finger rotates in a predetermined direction with respect to the rotation axis. , Fixed to the base. The drive unit is configured to rotate the movable finger at least in the predetermined direction.

  A shape of a portion of the first fixed finger facing the movable finger rotated in the predetermined direction at the time of closest approach; and the movable finger rotated in the predetermined direction of the second fixed finger; The shape of the portion facing when closest is different, the positional relationship between the first fixed finger and the rotating shaft is different from the positional relationship between the second fixed finger and the rotating shaft, or the movable finger is The shape of the portion of the movable finger that faces the first fixed finger when closest to the first fixed finger when rotated in the predetermined direction, and the second fixed finger and the outermost when the movable finger rotates in the predetermined direction. Depending on whether or not the shape of the portion of the movable finger facing when approaching is different, the shape of the gripping object that can be gripped between the first fixed finger and the movable finger rotated in the predetermined direction, Rotated in the predetermined direction with the second fixed finger Serial and shape of graspable gripping target between the movable fingers are different.

  Therefore, according to the present disclosure, even if only one movable finger is provided, the object to be grasped is grasped between the movable finger and the first fixed finger, or the movable finger and the second finger Different gripping objects can be gripped depending on whether the gripping object is gripped between the fixed finger. Accordingly, it is possible to grip various gripping objects using a small number of movable fingers.

  In addition, the code | symbol in the parenthesis described in this column and a claim shows the correspondence with the specific means as described in embodiment mentioned later as one aspect, Comprising: The technical scope of this invention is shown. It is not limited.

It is a bottom view showing the composition of the grasping device of a 1st embodiment. It is a top view showing the structure of the holding device. It is a side view showing the structure of the holding | gripping apparatus. It is the IV-IV sectional view taken on the line in FIG. It is explanatory drawing showing the 1st holding | grip operation | movement by the holding | grip apparatus. It is explanatory drawing showing the 2nd holding operation by the holding device. It is explanatory drawing showing the other example of the 2nd holding | grip operation | movement. It is a bottom view showing composition and operation of a grasping device of a 2nd embodiment. It is a bottom view showing the composition of the grasping device of a 3rd embodiment. It is sectional drawing showing the structure of the drive part in the holding | grip apparatus of 4th Embodiment. It is explanatory drawing showing the 1st holding | grip operation | movement by the holding | grip apparatus. It is a bottom view showing the composition of the grasping device of a 5th embodiment, and the 1st grasping operation. It is explanatory drawing showing the 2nd holding operation by the holding device. It is a bottom view showing the composition of the grasping device of a 6th embodiment. It is a side view which represents typically the structure of the principal part of the holding | gripping apparatus. It is a bottom view showing the composition of the grasping device of a 7th embodiment. It is explanatory drawing which represents typically the structure and operation | movement of the principal part of the holding | gripping apparatus. It is a bottom view showing the composition of the grasping device of an 8th embodiment. It is a graph showing the output characteristic of the strain gauge of the holding device. It is a bottom view showing the composition of the grasping device of a 9th embodiment. It is a fragmentary sectional view showing the composition of the grasping device. It is a bottom view showing the composition of the grasping device of a 10th embodiment, and the 1st grasping operation. It is a bottom view showing the 2nd grasping operation by the grasping device.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.
[1. First Embodiment]
[1-1. Constitution]
The gripping device 1 of the first embodiment shown in FIG. 1 includes a base 2, a first movable finger 3, a second movable finger 4, a first fixed finger 5, and a second fixed finger 6. Prepare. The base 2 has a substantially circular planar support surface 2A, and the first movable finger 3, the second movable finger 4, the first fixed finger 5, and the second fixed finger are formed on the surface of the support surface 2A. A finger 6 is provided.

  Note that the support surface 2A is often directed downward when the gripping device 1 grips a certain gripping object. However, the present invention is not limited to this, and the gripping device 1 is used so as to grip the object to be gripped with the support surface 2A facing upward or to grip the object to be gripped with the support surface 2A facing sideways. May be. In addition, as shown in FIG. 2, a fixing hole 2B (for example, a female hole) for mounting the base 2 on the tip of the arm of the robot or the like is formed on the surface of the base 2 opposite to the support surface 2A (hereinafter referred to as an upper surface). Screw hole) is formed. Furthermore, a drive unit 8 (for example, a motor) that rotates the first movable finger 3 and the second movable finger 4 via the speed reducer 7 is provided on the upper surface of the base 2. Furthermore, a hexagon socket head cap screw 11 that fixes the drive unit 8, the first fixed finger 5, and the second fixed finger 6 to the base 2 is screwed onto the upper surface. As schematically shown in FIG. 3, the drive unit 8 is connected to a control device 12 that rotates the drive unit 8 in an arbitrary direction.

  Returning to FIG. 1, the first movable finger 3 is rotatably mounted on the base 2 with respect to the first rotation shaft 13, and the outer peripheral surface thereof (that is, the outer peripheral surface of the support surface 2 </ b> A) is supported. It is curved in an arc shape along the outer peripheral surface of the surface 2A. The inner peripheral surface of the first movable finger 3 is also curved in an arc shape like the outer peripheral surface. The tip portion 3A as the free end of the first movable finger 3 is formed in a rounded shape (that is, having a curved end surface), and its apex is closer to the inner peripheral surface of the first movable finger 3. Located in.

  The second movable finger 4 is attached so as to be rotatable on the base 2 with respect to the second rotation shaft 14. The second rotating shaft 14 is provided on one end side of the base 2 together with the first rotating shaft 13, and is arranged adjacent to the first rotating shaft 13 with the second fixed finger 6 interposed therebetween. Similar to the first movable finger 3, the outer peripheral surface of the second movable finger 4 (that is, the outer peripheral surface of the support surface 2A) is also curved in an arc along the outer peripheral surface of the support surface 2A. The inner peripheral surface of the second movable finger 4 is also curved in an arc shape like the outer peripheral surface. The distal end portion 4 </ b> A as the free end of the second movable finger 4 is also configured in a rounded triangular shape, and the apex thereof is located near the inner peripheral surface of the second movable finger 4.

  As shown in FIGS. 3 and 4, the base end portion 3 </ b> B of the first movable finger 3 through which the first rotation shaft 13 passes is the thickness direction of the first movable finger 3 (that is, the rotation shafts 13, 14). It is comprised in the column shape extended over the whole. On the other hand, the other part of the movable finger 3 has a so-called comb-like structure composed of a plurality of layers 3C with a predetermined gap in the thickness direction. Similarly, in the second movable finger 4, the base end portion 4 </ b> B through which the second rotation shaft 14 penetrates is configured in a columnar shape extending over the entire thickness direction of the second movable finger 4. This portion has a comb-like structure composed of a plurality of layers 4C with a predetermined gap in the thickness direction.

  When the first movable finger 3 rotates in the clockwise direction in FIG. 1 (hereinafter referred to as a first direction: an example of a predetermined direction), each layer 3C of the first movable finger 3 becomes the second movable It is inserted into the gap between the layers 4C of the finger 4. Similarly, when the second movable finger 4 rotates in the counterclockwise direction (hereinafter, the second direction) in FIG. 1, each layer 4 </ b> C of the second movable finger 4 corresponds to each layer of the first movable finger 3. It is inserted into the gap of 3C.

  Further, as shown in FIG. 1, the first fixed finger 5 is fixed outside the rotation range of the first movable finger 3 and the rotation range of the second movable finger 4. Therefore, the first movable finger 3 can rotate on the support surface 2A within a range indicated by an arrow in FIG. That is, in the first direction, at least one of the layers 3C is in the second direction until at least one of the layers 3C is in contact with the proximal end portion 4B of the second movable finger 4. Each of them can be rotated until it comes into contact with the fixed finger 6. Similarly, in the second direction, the second movable finger 4 moves in the first direction until at least one of the layers 4C comes into contact with the proximal end portion 3B of the first movable finger 3. The rotation is possible until at least one of 4C comes into contact with the second fixed finger 6.

  The first rotating shaft 13 is constituted by a shaft-like member, and penetrates the base portion 2 and the base end portion 3 </ b> B of the first movable finger 3. A flange 13 </ b> A having a diameter larger than that of the rotation shaft 13 is rotatably provided integrally with the first rotation shaft 13 at an end portion of the first rotation shaft 13 on the first movable finger 3 side. The first rotating shaft 13 and the base end portion 3B of the first movable finger 3 are connected by an adhesive. For this reason, the 1st rotating shaft 13 and the 1st movable finger 3 rotate integrally. Similarly, the second rotating shaft 14 is also constituted by a shaft-like member, passes through the base 2 and the base end 4B of the second movable finger 4, and the flange 14A is integrated with the second rotating shaft 14. It is provided so as to be rotatable. Moreover, the 2nd rotating shaft 14 and the base end part 4B of the 2nd movable finger 4 are connected with the adhesive agent. For this reason, the 2nd rotating shaft 14 and the 2nd movable finger 4 rotate integrally.

  A pinion gear 17 is fixed to the base 2 side end of the first rotating shaft 13, and a pinion gear 18 is fixed to the base 2 side end of the second rotating shaft 14. The two pinion gears 17 and 18 mesh with a worm gear as the speed reducer 7. The reduction gear 7 may be constituted by a worm gear directly connected to the rotation shaft (that is, the output shaft) of the drive unit 8, and a reduction gear such as a reduction gear is further provided between the rotation shaft of the drive unit 8 and the worm gear. It may be provided with a mechanism.

  The control device 12 rotates the rotation shaft of the drive unit 8 in an arbitrary direction or stops the rotation shaft in accordance with an external command or the like. Therefore, the drive unit 8 rotates the second movable finger 4 in the second direction when rotating the first movable finger 3 in the first direction, and moves the first movable finger 3 in the second direction. When rotating in the direction, the second movable finger is rotated in the first direction.

  The line segment connecting the center of the first fixed finger 5 and the second fixed finger 6 is orthogonal to the line segment connecting the center of the first rotation shaft 13 and the center of the second rotation shaft 14. Yes. Further, the surface of the first fixed finger 5 that faces the second fixed finger 6, that is, the surface that faces the rotation range of the first movable finger 3 and the second movable finger 4 is the first fixed finger. It is configured in a substantially planar shape orthogonal to a line segment connecting the center of the finger 5 and the second fixed finger 6. More precisely, the surface is formed in a shape in which the central portion is slightly recessed along a cylindrical surface having an axis parallel to the first rotating shaft 13 and the second rotating shaft 14. On the other hand, the side surface of the second fixed finger 6 is formed in a substantially cylindrical surface shape including the surface facing the first fixed finger 5.

[1-2. Operation]
In the gripping device 1 configured as described above, the surface of the first fixed finger 5 facing the second fixed finger 6, that is, the first movable finger 3 and the second movable finger of the first fixed finger 5. The part which opposes 4 at the time of the closest approach is comprised by the substantially planar shape as mentioned above. For this reason, the side surface (that is, the surface extending in a long shape) of the long rectangular columnar gripping object 901 is brought into contact with the surface as shown in FIG. 5, and the first movable finger 3 and If the second movable finger 4 is brought into contact, the gripping object 901 can be gripped. At this time, the drive unit 8 rotates the first movable finger 3 in the first direction and rotates the second movable finger 4 in the second direction, thereby leading the tip of the first movable finger 3. The portion 3A and the tip portion 4A of the second movable finger 4 are brought into contact with the grasped object 901.

  If the first movable finger 3 is further rotated in the first direction and the second movable finger 4 is further rotated in the second direction, as shown in FIG. The object 902 can be gripped by sandwiching the cylindrical surface of the object 902 from the three sides with the first movable finger 3, the second movable finger 4, and the second fixed finger 6.

  If the first movable finger 3 is further rotated in the first direction and the second movable finger 4 is further rotated in the second direction, each layer 3C of the first movable finger 3 and the second The layers 4C of the movable fingers 4 are inserted into the gaps between them. Then, as shown in FIG. 7, the cylindrical surface of the cylindrical object 903 having a smaller diameter is sandwiched from the three sides by the first movable finger 3, the second movable finger 4, and the second fixed finger 6. The gripping object 903 can be gripped. 5 to 7, the shapes of the base 2, the first movable finger 3, the second movable finger 4, the first fixed finger 5, and the second fixed finger 6 are schematically shown.

[1-3. effect]
According to the first embodiment described in detail above, the following effects are obtained.
(1A) In the present embodiment, the portion of the first fixed finger 5 that faces the first movable finger 3 rotated in the first direction and the two movable fingers 4 rotated in the second direction at the time of closest approach. The shape is substantially planar. On the other hand, the shape of the portion of the second fixed finger that faces the first movable finger 3 rotated in the first direction or the second movable finger 4 rotated in the second direction at the time of closest approach is a cylinder. It is planar. Further, the positional relationship between the first fixed finger 5 and the first rotary shaft 13 and the second rotary shaft 14 is the same as that between the second fixed finger 6 and the first rotary shaft 13 and the second rotary shaft 14. Different from the positional relationship. As a specific positional relationship, the first fixed finger 5 is outside the rotation range of the first movable finger 3 and the second movable finger 4, while the second fixed finger 6 is the first movable finger. 3 and within the rotation range of the second movable finger 4. That is, the distances from the rotary shafts 13 and 14 to the closest positions of the fixed fingers 5 and 6 are different. Further, the directions from the rotary shafts 13 and 14 toward the closest positions of the fixed fingers 5 and 6 are also different. Further, the shape of the portion of the first movable finger 3 and the second movable finger 4 that faces the first fixed finger 5 when closest to the first movable finger 3 and the second fixed finger 6 of each of the movable fingers 3 and 4 is closest. Sometimes the shape of the opposing parts is different. Specifically, the former has a rounded triangular shape, whereas the latter has a cylindrical surface shape recessed with respect to the second fixed finger 6.

  For this reason, as described above, gripping that can be gripped between the first fixed finger 5, the first movable finger 3 rotated in the first direction, and the second movable finger 4 rotated in the second direction. Between the shape of the object (for example, the grasped object 901), the second fixed finger 6, the first movable finger 3 rotated in the first direction, and the second movable finger 4 rotated in the second direction The shape of the gripping object that can be gripped (for example, the gripping object 902 or 903) is different. Therefore, it is possible to grip various gripping objects using a small number of movable fingers 3 and 4. Therefore, it is possible to grip various gripping objects while suppressing the manufacturing cost of the gripping device 1.

  (1B) Further, in the present embodiment, the base 2 has a planar support surface 2A, and the first fixed finger 5 and the second fixed finger 6 are provided on the support surface 2A to perform the first rotation. The shaft 13 and the second rotary shaft 14 are set so as to be orthogonal to the support surface 2A, and the first movable finger 3 and the second movable finger 4 rotate on the support surface 2A with respect to the rotary shafts 13 and 14, respectively. To do. For this reason, the gripping object gripped between the first movable finger 3 and the second movable finger 4 and the first fixed finger 5 or the second fixed finger 6 is also supported by the support surface 2A. Thus, the object to be grasped can be grasped more stably.

  (1C) In this embodiment, the object to be grasped is grasped by three persons: the first movable finger 3, the second movable finger 4, and the first fixed finger 5 or the second fixed finger 6. Therefore, the object to be grasped can be grasped more stably.

  (1D) In the present embodiment, the first movable finger 3 and the second movable finger 4 are simultaneously rotated by the common drive unit 8. For this reason, the drive part 8 and the control apparatus 12 which controls the drive part 8 may be one system, and can suppress the manufacturing cost of the holding | grip apparatus 1 still more favorably.

  (1E) In this embodiment, a line segment connecting the center of the first fixed finger 5 and the center of the second fixed finger 6 connects the first rotating shaft 13 and the second rotating shaft 14. The first fixed finger 5 is disposed outside the rotation range of the first movable finger 3 and the rotation range of the second movable finger 4 and intersects with the connecting line segment, and the second fixed finger 6 is It is arranged inside the rotation range of the first movable finger 3 and the rotation range of the second movable finger 4. For this reason, the first movable finger 3 and the second movable finger 4 press one surface of the gripping object 901, and the first fixed finger 5 presses the other surface of the gripping object 901. And a second gripping operation in which the gripping object 902 and the like are sandwiched and gripped from three sides by the first movable finger 3, the second movable finger 4, and the second fixed finger 6 can be executed. .

  In particular, the first fixed finger 5 is disposed outside the rotation range of the first movable finger 3 and the rotation range of the second movable finger 4, and each layer 3C of the first movable finger 3 and the second Since each layer 4C of the movable finger 4 is inserted into the gap between each other, a gripping object having a small diameter like the gripping object 903 can be gripped by the second gripping operation. Therefore, the gripping device 1 of the present embodiment can grip an extremely wide variety of gripping objects.

  (1F) Further, in the present embodiment, the center of the first fixed finger 5 and the second on the vertical bisector connecting the center of the first rotating shaft 13 and the center of the second rotating shaft 14. The center of the fixed finger 6 exists. For this reason, the configuration of the gripping device 1 is symmetric with respect to a plane that includes the vertical bisector and is orthogonal to the support surface 2A. Accordingly, the gripping operation related to the first movable finger 3 and the second movable finger 4 can be easily controlled.

  (1G) In the present embodiment, the first fixed finger 5 is relatively close to each rotation range outside the rotation range of the first movable finger 3 and the rotation range of the second movable finger 4. In the position. For this reason, even if the gripping object 901 is thin, the first gripping operation as described above can be executed. Therefore, the gripping device 1 of the present embodiment can grip a wider variety of gripping objects.

  (1H) In the present embodiment, the second fixed finger 6 is provided adjacently between the first rotating shaft 13 and the second rotating shaft 14. More specifically, the outer peripheral surfaces of the first rotary shaft 13 and the second rotary shaft 14 and the first rotary shaft 14 are shorter than the shortest distance between the outer peripheral surface of the second fixed finger 6 and the outer peripheral surface of the first fixed finger 5. The shortest distance from the outer peripheral surface of one fixed finger 5 is shorter. For this reason, in combination with the configuration in which each layer 3C of the first movable finger 3 and each layer 4C of the second movable finger 4 are inserted into the gap between each other, the gripping object having a smaller diameter also has the second gripping operation. Can be gripped well.

  (1I) In the present embodiment, the first movable finger 3 is located on the side farther from the proximal end portion 3B on the side closer to the rotation shaft 13 when viewed along the axial direction of the first rotation shaft 13. It is configured in a shape curved along the first rotation direction toward the distal end portion 3A. Similarly, when the second movable finger 4 is viewed along the axial direction of the second rotation shaft 14, the second movable finger 4 is directed toward the distal end portion 4 </ b> A far from the base end portion 4 </ b> B near the rotation shaft 14. It is comprised in the shape curved along the said 2nd rotation direction.

  For this reason, when a long gripping object such as the gripping object 901 is gripped between the first fixed finger 5 and the movable finger 3, 4 end portions 3A and 4A can be brought into contact with each other, and the object to be grasped can be more stably grasped. In addition, when the first movable finger 3, the second movable finger 4, and the second fixed finger 6 hold the object 902 etc. sandwiched from three sides, the inner peripheral surface of the movable fingers 3, 4 is the object to be grasped. The object 901 or the like can be brought into contact with the outer peripheral surface in a state close to surface contact, and the object to be grasped can be grasped more stably.

  (1J) Moreover, in this embodiment, the front-end | tip parts 3A and 4A of each movable finger 3 and 4 are comprised by the rounded triangular shape. Therefore, in combination with the configuration described in (1I), when a long gripping object such as the gripping object 901 is gripped with the first fixed finger 5, the gripping target object Regardless of the thickness, the tip portions 3A and 4A are in contact with the side surface of the object to be grasped in a state close to surface contact. That is, even if the contact angles between the movable fingers 3 and 4 and the object to be grasped are different, almost the same grasping force can be obtained. Therefore, regardless of the thickness of the gripping object, the gripping object can be gripped more stably.

[2. Second Embodiment]
[2-1. Difference from the first embodiment]
Since the basic configuration of the second embodiment is the same as that of the first embodiment, differences will be described below. Note that the same reference numerals as those in the first embodiment indicate the same configuration, and the preceding description is referred to.

  In 1st Embodiment mentioned above, the outer peripheral surface of the 1st movable finger 3, the 2nd movable finger 4, and the 2nd movable finger 4 is comprised by circular arc shape. On the other hand, as shown in FIG. 8, the gripping device 21 of the second embodiment has a first notch 23 </ b> E formed on the outer peripheral surface of the first movable finger 23, and the outer periphery of the second movable finger 24. The difference is that a second notch 24E is formed on the surface. That is, the first notch 23E is formed on the side surface that becomes the head when the movable finger 23 in the first movable finger 23 rotates in the second direction, and the movable finger in the second movable finger 24 is formed. A second notch 24E is formed on the side surface that becomes the top when the 24 rotates in the first direction. In addition, these notches 23E and 24E are formed so that the first movable finger 23 rotates in the second direction and the second movable finger 24 moves in the first direction, as indicated by phantom lines in FIG. When rotated, they are formed at positions that face each other and that can hold the object 904 between them.

[2-2. effect"
According to 2nd Embodiment described above, there exist the effects (1A)-(1J) of 1st Embodiment mentioned above, and also there exist the following effects.

  (2A) In the present embodiment, it is possible to grip the gripping object 904 or the like between the notches 23E and 24E, that is, between the outer peripheral surfaces of the movable fingers 23 and 24. For this reason, it is possible to grip a wider variety of gripping objects.

[3. Third Embodiment]
[3-1. Difference from the first embodiment]
Since the basic configuration of the third embodiment is the same as that of the first embodiment, differences will be described below. Note that the same reference numerals as those in the first embodiment indicate the same configuration, and the preceding description is referred to.

  In the first embodiment described above, the support surface 2A in the base 2 is a flat surface without holes or the like. In contrast, in the gripping device 31 of the third embodiment, as schematically shown in FIG. 9, the base portion 32 has an opening 32 </ b> E at a portion facing the rotation range of the movable fingers 3, 4, and the support surface. 32A also differs in that it is open at that portion. In addition, in FIG. 9, although the shape of the base 2, the 1st movable finger 3, the 2nd movable finger 4, the 1st fixed finger 5, and the 2nd fixed finger 6 is shown typically, these shapes are shown. May be the same as the gripping device 1 of the first embodiment.

[3-2. effect"
According to 3rd Embodiment described above, there exist the effects (1A)-(1J) of 1st Embodiment mentioned above, and also there exist the following effects.

  (3A) In the present embodiment, in the state where the opening 32E is passed through the grasped object, the grasped object is moved to the first movable finger 3 and the second movable finger 4, the first fixed finger 5 or the second fixed finger. And can be held between the fixed fingers 6. For this reason, it is possible to grip a wider variety of gripping objects.

  (3B) Further, since the second fixed finger 6 is provided between the first rotating shaft 13 and the second rotating shaft 14, the area of the opening 32E into which the grasped object can be inserted is improved. The gripping operation as shown in FIGS. 6 and 7 can be performed more satisfactorily.

[4. Fourth Embodiment]
[4-1. Difference from the first embodiment]
Since the basic configuration of the fourth embodiment is the same as that of the first embodiment, differences will be described below. Note that the same reference numerals as those in the first embodiment indicate the same configuration, and the preceding description is referred to.

  In the first embodiment described above, the first movable finger 3 and the second movable finger 4 are simultaneously rotated by one drive unit 8. On the other hand, as shown in FIG. 10, the gripping device 41 of the fourth embodiment has a drive unit 48 (for example, for rotating them individually with respect to the first rotating shaft 13 and the second rotating shaft 14). , Motor) is directly attached.

[4-2. effect"
According to the fourth embodiment described above, the effects (1A) to (1C) and (1E) to (1J) of the first embodiment described above are exhibited, and the following effects are further achieved.

  (4A) In the present embodiment, the first movable finger 3 and the second movable finger 4 can be arbitrarily rotated individually. For this reason, like the gripping object 910 shown in FIG. 11, the gripping object having the thin part 911 and the thick part 912 (that is, partly tapered) is gripped by the first gripping operation. Can also be easily implemented. In other words, the movable fingers 3 and 4 can be individually rotated to an angle corresponding to the thickness of the portion of the grasped object that abuts. Therefore, in this embodiment, it is possible to grip a wider variety of gripping objects more stably.

[5. Fifth Embodiment]
[5-1. Difference from the first embodiment]
Since the basic configuration of the fifth embodiment is the same as that of the first embodiment, differences will be described below. Note that the same reference numerals as those in the first embodiment indicate the same configuration, and the preceding description is referred to.

  In the first embodiment described above, the second fixed finger 6 is provided between the first rotating shaft 13 and the second rotating shaft 14. On the other hand, as schematically shown in FIGS. 12 and 13, the gripping device 51 of the fifth embodiment has a first fixed finger 5 further than the arrangement of the second fixed finger 6 in the first embodiment. Is different in that the second fixed finger 6 is provided at a position close to. 12 and 13 schematically illustrate the shapes of the base 2, the first movable finger 3, the second movable finger 4, the first fixed finger 5, and the second fixed finger 6. These shapes may be the same as the gripping device 1 of the first embodiment.

[5-2. effect"
According to the fifth embodiment described above, the effects (1A) to (1G) (1I) (1J) of the first embodiment described above are exhibited, and further, the following effects are achieved.

  (5A) In the gripping device 51 of the present embodiment, as shown in FIG. 12, a long gripping object 913 between the first movable finger 3 and the second movable finger 4 and the first fixed finger 5 is used. The first gripping operation for gripping the etc. can be executed in the same manner as the gripping device 1 of the first embodiment. On the other hand, as shown in FIG. 13, the first movable finger 3, the second movable finger 4, and the second fixed finger 6 hold the cylindrical gripping object 914 and the like from three sides. The second gripping operation can be executed at a position closer to the first fixed finger 5 than in the first embodiment. Thereby, it becomes possible to grip a small-diameter gripping object without taking the comb-tooth structure of the first embodiment, and the manufacturing cost of the gripping device 51 can be further suppressed. That is, also in this embodiment, if a comb-tooth structure provided with the layers 3C and 4C is employed as in the first embodiment, a gripping object having a smaller diameter can be gripped. However, in this embodiment, even if such a comb-tooth structure is not employed, a gripping object having a smaller diameter can be gripped compared to the case where the comb-tooth structure is not employed in the first embodiment.

[6. Sixth Embodiment]
[6-1. Difference from the first embodiment]
Since the basic configuration of the sixth embodiment is the same as that of the first embodiment, differences will be described below. Note that the same reference numerals as those in the first embodiment indicate the same configuration, and the preceding description is referred to.

  As shown in FIG. 14, the gripping device 61 according to the present embodiment has a surface pressure sensor 69 (for example, a surface piezoelectric body or a semiconductor sensor) attached to the outer periphery of the first movable finger 63. This is different from the first embodiment. In addition, in FIG. 14, although the shape of the base 2, the 1st movable finger 63, the 2nd movable finger 64, the 1st fixed finger 5, and the 2nd fixed finger 6 is shown typically, these shapes are shown. May be the same as the gripping device 1 of the first embodiment.

  More specifically, in the present embodiment, the layer 64C of the second movable finger 64 is in the axial direction of the base end portion 64B (that is, the rotary shafts 13 and 14 as schematically shown in FIG. The two axial layers are formed at both ends with the same thickness as the layer 4C in the first embodiment. The first movable finger 63 is formed as a single layer having a thickness that can be inserted between the two layers 64C with a slight margin, and is formed at the axial center of the base end portion 63B. . A planar pressure sensor 69 is attached to the surface of the first movable finger 63 configured to be thick so as to cover at least a contact position with various gripping objects. Since the 1st movable finger 63 is comprised thickly, the planar pressure sensor 69 grade | etc., Can be stuck easily.

[6-2. effect"
According to the sixth embodiment described above, the effects (1A) to (1J) of the first embodiment described above are exhibited, and the following effects are further achieved.

  (6A) In the gripping device 61 of the present embodiment, a load applied to the first movable finger 63 from the gripping target can be detected via the pressure sensor 69. For this reason, the torque applied to the movable fingers 63 and 64 from the drive unit 8 can be appropriately controlled, and the object to be gripped can be gripped with appropriate strength. In the present embodiment, the pressure sensor 69 corresponds to a detection unit.

[7. Seventh Embodiment]
[7-1. Difference from the sixth embodiment]
Since the basic configuration of the seventh embodiment is the same as that of the sixth embodiment, differences will be described below. Note that the same reference numerals as those in the sixth embodiment denote the same components, and the preceding description is referred to.

  In the gripping device 61 of the sixth embodiment, a pressure sensor 69 is attached to the surface of the first movable finger 63. On the other hand, in the gripping device 71 of the present embodiment, as shown in FIG. 16, a rubber part 79 having a sealed hollow space is attached to the surface of the first movable finger 63. A barometric pressure sensor 78 is provided at the base end portion 63 </ b> B of the first movable finger 63. As schematically shown in the diagram on the left side in FIG. 17, the atmospheric pressure sensor 78 detects the atmospheric pressure in the hollow space of the rubber part 79. For this reason, as schematically shown in the diagram on the right side in FIG. 17, when the gripping object 915 is gripped by the first movable finger 63 and the rubber part 79 is pushed by the gripping object 915 to be recessed, the hollow space The atmospheric pressure increases. For this reason, based on the atmospheric pressure detected by the atmospheric pressure sensor 78, the load applied to the first movable finger 63 from the grasped object 915 can be detected.

[7-2. effect"
According to the seventh embodiment described above, the effects (1A) to (1J) of the first embodiment and the effect (6A) of the sixth embodiment described above are obtained as in the gripping device 61 of the sixth embodiment. . In the present embodiment, the rubber part 79 and the atmospheric pressure sensor 78 correspond to a detection part.

[8. Eighth Embodiment]
[8-1. Difference from the sixth embodiment]
Since the basic configuration of the eighth embodiment is the same as that of the sixth embodiment, differences will be described below. Note that the same reference numerals as those in the sixth embodiment denote the same components, and the preceding description is referred to.

  In the gripping device 61 of the sixth embodiment, a pressure sensor 69 is attached to the surface of the first movable finger 63. On the other hand, the gripping device 81 of this embodiment is different in that a strain sensor 89 (for example, a strain gauge) is attached to the surface of the first movable finger 83 as shown in FIG. More specifically, the first movable finger 83 is configured to have the same thickness as the first movable finger 63 in the sixth embodiment, but a rectangular notch 83F is provided at a portion where the strain sensor 89 is attached. Is formed. That is, the strain sensor 89 is attached to a location where the notch 83F reduces the moment of inertia of the cross section and the load applied from the grasped object is easily reflected as strain.

  19 shows the output voltage of the strain sensor 89 and the rotation shaft 13 when a load in the direction of the arrow is applied to the point A, B, or C in FIG. 18 set on the tip side from the notch 83F with a pull gauge. The relationship of such torque is shown. It can be seen that the output voltage and the torque have the same proportional relationship at any point, and that the torque (that is, the load applied from the grasped object) can be measured by this method. In FIG. 19, □ represents the relationship when a load is applied to the point A, Δ represents the relationship when a load is applied to the point B, and ◇ represents a load applied to the point C. The relationship when added is shown.

[8-2. effect"
According to the eighth embodiment described above, the effects (1A) to (1J) of the first embodiment and the effect (6A) of the sixth embodiment described above are obtained as in the gripping device 61 of the sixth embodiment. . In the present embodiment, the strain sensor 89 corresponds to a detection unit.

[9. Ninth Embodiment]
[9-1. Difference from Eighth Embodiment]
Since the basic configuration of the ninth embodiment is the same as that of the eighth embodiment, differences will be described below. Note that the same reference numerals as those in the eighth embodiment indicate the same configuration, and the preceding description is referred to.

  In the gripping device 81 of the eighth embodiment, the strain sensor 89 is attached to the notch 83F formed in the first movable finger 83. On the other hand, in the gripping device 91 of this embodiment, as schematically shown in FIGS. 20 and 21, the first movable finger 93 is formed with a bottomed hole 93 </ b> G so that the first movable The difference is that the finger 93 has a hollow structure and a strain sensor 99 is attached to the inner wall surface of the bottomed hole 93G. In more detail, the strain sensor 99 includes an inner wall surface on the leading side when the first movable finger 93 rotates in the first direction, and the first movable finger 93 rotates in the second direction. Are provided on the inner wall surface on the side that becomes the head when the operation is performed. Each strain sensor 99 is provided at a position near the base end portion 93B on each inner wall surface.

[9-2. effect"
Also in this case, the load applied to the movable finger 93 from the grasped object can be measured based on the output voltage of the strain sensor 99. Therefore, according to the ninth embodiment described above, similarly to the gripping device 61 of the sixth embodiment, the effects (1A) to (1J) of the first embodiment and the effect (6A) of the sixth embodiment described above. Play. In the present embodiment, the strain sensor 99 corresponds to a detection unit. Further, the movable fingers 63 to 94 in the sixth to ninth examples may be provided with notches similar to the notches 23E and 24E in the second embodiment.

[10. Tenth Embodiment]
[10-1. Differences from the first to ninth embodiments]
In the first to ninth embodiments described above, the first movable finger and the second movable finger are provided as movable fingers, but the gripping device 101 of the tenth embodiment shown in FIG. It differs from each said embodiment by the point provided with only one. In the present embodiment, a base 102 having a substantially circular planar support surface 102A is provided with a rotating shaft 113 that vertically penetrates the support surface 102A. Although not shown, the rotary shaft 113 is directly connected to the drive unit 48 and driven to rotate as in the fourth embodiment. One end (that is, the base end portion) of the movable finger 103 configured in a long rectangular parallelepiped shape is connected to the rotation shaft 113. For this reason, the movable finger 103 rotates integrally with the rotation shaft 113.

  The first fixed finger 105 configured in the same manner as the first fixed finger 5 is fixed outside the rotation range of the movable finger 103. Further, as described above, the substantially fixed surface 105A of the first fixed finger 105 having a slightly recessed central portion faces the side surface of the movable finger 103 when the movable finger 103 is disposed at a predetermined rotational position. As described above, the first fixed finger 105 is fixed on the support surface 102A.

  Further, as in the first embodiment, the second fixed finger 106 configured in a columnar shape is fixed on the support surface 102 </ b> A inside the rotation range of the movable finger 103. Further, the direction from the rotation shaft 113 toward the center of the first fixed finger 105 is different from the direction from the rotation shaft 113 toward the center of the second fixed finger 106.

  For this reason, by arranging the movable finger 103 at the predetermined rotation position described above, a rectangular parallelepiped gripping object 916 is gripped between the first fixed finger 105 and the movable finger 103 as shown in FIG. can do. Further, a grasping object 920 having a notch 921 on one side surface and a flat surface portion 922 on the other side surface can be grasped by the grasping device 101 as shown in FIG. That is, the notch 921 is engaged with the second fixed finger 106 and the flat portion 922 is pressed by the side surface of the movable finger 103 so that the notch 921 can be held between the second fixed finger 106 and the movable finger 103. it can.

[10-2. effect]
According to the tenth embodiment described above, the effects (1A) and (1B) of the first embodiment described above can be achieved, and further the following effects can be achieved.

  (10A) The gripping device 101 of the present embodiment includes only one movable finger 103 as a movable finger. Therefore, the configuration is simplified, and the manufacturing cost of the gripping device 101 can be reduced extremely well.

[11. Other Embodiments]
As mentioned above, although the form for implementing this indication was demonstrated, this indication is not limited to the above-mentioned embodiment, and can carry out various modifications.

  (11A) The shapes of the base, the movable finger, the first movable finger, the second movable finger, the first fixed finger, the second fixed finger, etc. are not limited to the shapes exemplified in the above embodiments. Absent. For example, in FIG. 9 and the like, the shapes of the base, the first movable finger, the second movable finger, the first fixed finger, and the second fixed finger are schematically shown. The shape as shown in FIG. That is, the first movable finger 3 and the second movable finger 4 may be configured in a straight line, and the second fixed finger 6 may be configured in a columnar shape. Further, the first fixed finger and the second fixed finger may have the same shape. These shape changes can be similarly performed for the first embodiment and the second embodiment.

  (11B) In each of the above embodiments, the rotating shaft is configured as a member independent of the base, the movable finger, the first movable finger, the second movable finger, and the like, but is not limited thereto. The rotation axis may be set with respect to the base in some form. For example, the rotating shaft may be a boss provided on the base or the movable finger, and may not exist as a shaft member.

  (11C) In each of the above embodiments, the movable object or the first movable finger and the grasped object that can be grasped by the method sandwiched between the second movable finger and the first fixed finger, and the movable finger or the first Although the example in which the gripping object that can be gripped by the method of being sandwiched between the movable finger and the second movable finger and the first fixed finger is different is shown, the present invention is not limited to this. There may be a gripping object that can be gripped by any of the above methods.

  (11D) In each of the embodiments described above, a motor or the like is assumed as the drive unit, but the present invention is not limited to this. As the drive unit, a configuration using a solenoid or the like can be adopted, a configuration using an elastic body such as a spring or rubber and a stopper can be adopted, and other configurations can be adopted. Is also possible. In the latter case, the movable finger may be rotated in the first direction by the biasing force of the elastic body by removing the stopper, and may be manually returned in the second direction. However, when the meshing between the worm gear and the pinion gear is used as in the first embodiment, the force applied to the movable finger is not easily transmitted as the force that rotates the rotating shaft of the motor, and the object to be grasped can be grasped more stably. Can do. Moreover, in order to hold | grip the holding object 910 like 4th Embodiment, mechanisms, such as a differential gear, may be applied instead of providing multiple drive parts.

  (11E) In each of the embodiments described above, the gripping device attached to the tip of the robot arm or the tip of the manipulator has been described. However, the present invention is not limited to this. For example, the present disclosure can also be applied to a gripping device attached to the tip of a hand for the handicapped. In addition, the present disclosure can be applied to various gripping devices that grip some gripping object.

  (11F) A plurality of functions of one constituent element in the embodiment may be realized by a plurality of constituent elements, or one function of one constituent element may be realized by a plurality of constituent elements. . Further, a plurality of functions possessed by a plurality of constituent elements may be realized by one constituent element, or one function realized by a plurality of constituent elements may be realized by one constituent element. Moreover, you may abbreviate | omit a part of structure of the said embodiment. In addition, at least a part of the configuration of the embodiment may be added to or replaced with the configuration of the other embodiment. In addition, all the aspects included in the technical idea specified only by the wording described in the claim are embodiment of this invention.

21, 31, 41, 51, 61, 71, 81, 91, 101 ... gripping device 2, 32, 102 ... base 2A, 32A, 102A ... support surface 3, 23, 63, 83, 93 ... first movable finger 3A, 4A ... tip 3B, 4B, 63B, 64B, 93B ... base end 3C, 4C, 64C ... layer 4, 24, 64 ... second movable finger 5, 105 ... first fixed finger 6, 106 ... Second fixed finger 8, 48 ... Driving unit 12 ... Control device 13 ... First rotating shaft 14 ... Second rotating shaft 23E ... First notch 24E ... Second notch 32E ... Opening 69 ... Pressure Sensor 78 ... Barometric pressure sensor 79 ... Rubber part 83F ... Notch 89, 99 ... Strain sensor 93G ... Bottomed hole 103 ... Movable finger 113 ... Rotating shaft

Claims (14)

The base (2,102);
Movable fingers (3, 23, 63, 83, 93, 103) provided to be rotatable in an eccentric manner with respect to the rotation shafts (13, 113) set in the base;
When the movable finger rotates in a predetermined direction with respect to the rotation axis, a first fixed finger (positioned at a position for gripping a gripping object between the movable finger and the fixed finger) 5, 105) and a second fixed finger (6, 106);
A drive unit (8, 48) configured to rotate the movable finger at least in the predetermined direction;
With
The shape of the portion of the first fixed finger that faces the movable finger that is rotated in the predetermined direction at the time of closest approach, and the closest approach of the movable finger that is rotated in the predetermined direction in the second fixed finger. Sometimes the shape of the opposed parts is different, the positional relationship between the first fixed finger and the rotating shaft is different from the positional relationship between the second fixed finger and the rotating shaft, or the movable finger is the predetermined The shape of the portion of the movable finger that faces the first fixed finger when approaching closest to the first fixed finger and the second fixed finger when approaching closest when the movable finger rotates in the predetermined direction The shape of the graspable object that can be grasped between the first fixed finger and the movable finger rotated in the predetermined direction, depending on whether or not the shape of the part of the movable finger facing the second finger is different, and the second The fixed finger and the allowable finger rotated in the predetermined direction. Different gripping device and the shape of the grippable grasped object between the fingers. The gripping device according to claim 1,
The base has a planar support surface (2A, 102A),
The first fixed finger and the second fixed finger are provided on the support surface;
The rotation axis is set to be orthogonal to the support surface;
The gripping device configured to rotate the movable finger on the support surface with respect to the rotation axis. The gripping device according to claim 1 or 2,
The movable finger (3, 23, 63, 83, 93) is a first movable finger,
The rotating shaft (13) is a first rotating shaft;
The predetermined direction is a first direction;
The base (2) is provided so as to be rotatable in a state of being eccentric with respect to the second rotating shaft (14) set in parallel to the first rotating shaft, and is opposite to the first direction. A second movable finger configured to grip a gripping object between the first fixed finger or the second fixed finger when rotated with respect to the second rotation axis in the direction of 4, 24, 64)
In addition,
A shape of a graspable object that can be grasped between the first fixed finger, the first movable finger rotated in the first direction, and the second movable finger rotated in the second direction; The shape of the graspable object that can be grasped is different between the second fixed finger, the first movable finger rotated in the first direction, and the second movable finger rotated in the second direction. Gripping device. The gripping device according to claim 3,
The gripping device configured to rotate the second movable finger in the second direction when the drive unit (8) rotates the first movable finger in the first direction. The gripping device according to claim 3,
The driving unit (48) is a first driving unit,
A second drive unit (48) configured to rotate the second movable finger in the second direction independently of the first movable finger;
A gripping device further provided. The gripping device according to any one of claims 3 to 5,
A line segment connecting the center of the first fixed finger and the center of the second fixed finger intersects a line segment connecting the first rotation axis and the second rotation axis, and the first The fixed finger is disposed outside the rotational range of the first movable finger and the rotational range of the second movable finger, and the second fixed finger is configured to rotate the rotational range of the first movable finger and the first movable finger. A gripping device disposed inside the rotation range of the two movable fingers. The gripping device according to any one of claims 3 to 6, wherein
The first movable finger, when viewed along the axial direction of the first rotating shaft, has a distal end portion (3A) farther from the proximal end portion (3B, 63B, 93B) closer to the rotating shaft. ) Is formed in a shape curved along the first direction,
When the second movable finger is viewed along the axial direction of the second rotation shaft, the distal end portion (4A) farther from the proximal end portion (4B, 64B) closer to the rotation shaft. A gripping device configured to be curved along the second direction. The gripping device according to any one of claims 3 to 7,
At least one of the first movable finger and the second movable finger (3, 4, 23, 24, 64) is formed in a plurality of layers with a gap in the axial direction of each of the rotation shafts. Configured,
The other of the first movable finger or the second movable finger (3, 4, 23, 24, 63, 83, 93) is at least in response to rotation in the first direction or the second direction. A gripping device configured to be partially inserted into the gap. The gripping device according to claim 8, wherein
The gripping device in which any one layer of the movable fingers configured in the plurality of layers or the movable fingers (63, 83, 93) inserted in the interval is configured to be thicker than the other layers in the axial direction. The gripping device according to any one of claims 3 to 9,
The drive unit is configured to rotate the first movable finger in the second direction and to rotate the second movable finger in the first direction;
When the movable finger of the first movable finger (23) rotates in the second direction, a first notch (23E) formed on a side surface on the leading side and the second movable finger ( A second notch (24E) formed on a side surface on the leading side when the movable finger in 24) rotates in the first direction,
When the first movable finger rotates in the second direction and the second movable finger rotates in the first direction, the first notch and the second notch are A gripping device configured to be capable of gripping a gripping object between the two facing each other. The gripping device according to any one of claims 1 to 10,
A detection unit (69, 78, 79, 89, 99) configured to detect a load applied to the movable finger (63, 83, 93) from a gripping object;
A gripping device further provided. The gripping device according to claim 11,
The gripping device, wherein the detection unit is a planar pressure sensor (69) attached to the surface of the movable finger (63). The gripping device according to claim 11,
The detection part is attached to the surface of the movable finger (63), and has a rubber part (79) having a sealed hollow space, and an atmospheric pressure sensor (78) configured to detect the atmospheric pressure in the hollow space. And a gripping device. The gripping device according to claim 11,
The gripping device, wherein the detection unit is a strain sensor (89, 99) configured to detect strain of the movable finger (83, 93).

Images