JP2017074638A - End effector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an end effector capable of gripping both a hole and the outer periphery that are a part external shape by a set of gripping claws in accordance with a part of a different bulked attitude in a part box, and also relieving impact to a gripping mechanism and a robot even when abutting on the part box.SOLUTION: An end effector comprises a gripping claw 7 for gripping a part, a gripping mechanism having a chuck opening/closing mechanism 20 for opening and closing the gripping claw and a compliance device for exhibiting a compliance property, and in the end effector, the gripping claw is formed in a tapering-off shape toward a tip part. An outer peripheral surface 34 except for an opposed surface of a first claw piece 7a and a second claw piece 7b of the tip part is formed in a substantially hemispherical shape, and an inner flange part 30 is formed in a lower end part of the opposed surface of the first claw piece and the second claw piece. A recessed part is formed on one side of the opposed surface of its inner flange part, and a projection part is also formed on the other side. An outer flange part 31 is formed on the outer peripheral surface side on the opposite side of an inner jaw part of the first claw piece and the second claw piece, and an adapter 8 is interposed for connecting the chuck opening/closing mechanism and the gripping claw.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a gripping claw that is attached to the tip of an arm of a robot and that grips a component one by one from among a plurality of components that are stored in a complicated state mainly in a component box, and a chuck that is responsible for opening and closing the gripping claw. The present invention relates to an opening / closing mechanism and an end effector including a compliance device that exhibits compliance with impact.

  Production lines such as automobile manufacturing factories are required to operate 24 hours a day in order to shorten the capital investment recovery period. To that end, a technology has been developed to take out and transport parts stored in bulk in the parts box supplied to the production line with a robot. Technology related to a mechanism for gripping one by one has been developed.

  For example, in Patent Document 1, as a compliance device, a pair of brackets respectively attached to a holding part and a support part, and a through hole provided in one bracket are passed through, and one bracket is attached to the other bracket. A guide shaft that is movably supported so as to be close to and away from each other, and a biasing means that applies a biasing force so that both brackets are separated from each other, and the diameter of the guide shaft is the same as that of the through hole And a compliance device having a small diameter constricted portion smaller than the diameter of the through hole is disclosed. Further, FIG. 4 of Patent Document 1 describes a gripping claw that forms a linear shape for gripping a bolt.

  Patent Document 2 includes a robot hand having a structure in which a chuck having a rigid gripping claw is movable with respect to a hand body, and the chuck is supported on the hand body via an elastic body in the moving direction. A method for taking out a workpiece to be grasped using the robot, wherein the gripping claw is pressed against the target workpiece until the elastic body is compressed by a predetermined amount, and the gripping claw applies a preload to the workpiece to be grasped. An unloading method is disclosed in which the gripping claw is inserted in the vicinity of the side of the workpiece to be gripped by opening the chuck in a state. Further, FIG. 3 of Patent Document 2 describes a gripping claw in which the overall shape is a linear shape and the tip portion is bent inward.

  Patent Document 3 discloses a compliance module that compensates for a positional deviation of a finger module that is attached to a robot hand and grips a workpiece, and that rotates horizontally in compliance with X and Y directions orthogonal to each other. In a compliance module that executes a compliance operation in the θ direction, a neutral position holding mechanism that is slidably or pivotably connected to each plate in each movement direction and that returns the movement. A compliance module is disclosed.

  In Patent Document 4, in order to hold the end of a columnar or cylindrical part at the tip of two flat pawl bodies that can be opened and closed, it penetrates in the plate thickness direction, and its inner side surface is A pair of recesses extending in the plate thickness direction is formed, and a pair of recesses penetrating in the plate thickness direction in the same manner as the side edges of the claw body and the inner side surfaces thereof extending in the plate thickness direction are formed. Thus, there is disclosed a robot hand that can hold an end portion of a component from both vertically upward and horizontal sides.

Japanese Patent No. 5706585 Japanese Patent No. 5383847 Japanese Patent No. 4684160 Japanese Patent No. 3527028

  In the invention described in Patent Document 1, a gap is generated between the outer peripheral wall of the small diameter portion of the guide shaft and the inner peripheral wall of the hole portion having a diameter larger than the diameter of the small diameter portion of the bracket. There is a problem that the compliance device is liable to be damaged because the small-diameter portion is liable to be cracked due to repetitive stress caused by the collision with the guide shaft. Further, in the case where the length of the small diameter portion of the guide shaft is short, there is a problem that the amount of displacement in the vertical direction is insufficient and a shearing force is repeatedly applied to the small diameter portion of the guide shaft, and the small diameter portion is likely to crack. It was.

  Further, in the shape of the gripping claw described in FIG. 4 of Patent Document 1, since the tip of the gripping claw is straight, a lightweight part can be gripped, but a heavy part slips from the claw when trying to grip it. There was a problem that it could not be gripped.

  Since the invention described in Patent Document 2 has a structure that exhibits only compliance in one direction, for example, the vertical direction, there is a problem in that compliance cannot be exhibited when the gripping claw collides with the component box from the lateral direction. It was.

  In addition, in the shape of the gripping claw described in FIG. 3 of Patent Document 2, it is possible to grip the component with the gripping claw from the outside, but the gripping claw is inserted into the hole of the component. There was a problem that it could not be gripped.

  The invention described in Patent Document 3 has a problem that the structure becomes complicated and the manufacturing cost increases because independent mechanisms such as a compliance mechanism in the X-axis direction and a compliance mechanism in the Y-axis direction are provided for each axial direction. Since the compliance with the X-axis direction, the Y-axis direction, and the horizontal rotation direction is exhibited, the plate is tilted in three dimensions, which occurs when the tip of the robot hand hits the component box from an oblique direction. In such a case, there was a problem that sufficient compliance could not be exhibited.

  The invention described in Patent Document 4 has a problem that since the gripping claw has a flat plate shape, the component cannot be gripped in the case of a component that cannot be gripped unless inserted into the small hole portion of the component.

  The present invention has been conceived in view of these problems, and a gripping claw can be inserted into a small hole portion of a component and can grip an edge portion of the hole portion, or a gripping claw can be gripped by sandwiching an outer edge portion of the component. In addition, the end effector that grips the parts one by one from the multiple parts that are stored in a complicated manner in the parts box of the parts may be displaced and contact the parts box or parts. Another object of the present invention is to provide an end effector that can alleviate the impact on the end effector and the robot, can securely grip the component, is less likely to stop, and is less prone to repeated fatigue.

  The end effector 1 according to claim 1 is an end effector 1 attached to a tip of a robot arm 4 for picking a component 5, and the end effector 1 includes a gripping mechanism 2 for gripping a component, and the robot arm 4. And a compliance device 3 that exhibits compliance when an external force P is applied to the gripping mechanism 2. The gripping mechanism 2 includes a pair of first and second arms 21a and 21b that open and close. And a chuck opening / closing mechanism 20 having a driving cylinder 22 connected to the chuck arm 21 to open and close the chuck arm 21, and an opening / closing mechanism that opens and closes to each other by the operation of the driving cylinder 22. The first claw piece 7a interlocked with the operation of the first arm 21a, A pair of gripping claws 7 composed of a second claw piece 7b interlocked with the operation of the second arm 21b, and the first claw piece 7a and the second claw piece 7b of the pair of gripping claws 7 are the chuck arms. A tapered shape is formed from the attachment portion 21 toward the tip portion, and the outer peripheral surface 34 of the tip portion other than the facing surfaces of the first claw piece 7a and the second claw piece 7b forms a substantially hemispherical shape. Then, the lower end portions of the opposing surfaces of the first claw piece 7a and the second claw piece 7b are protruded to the opposite side to form the inner collar portion 30, and the inner sides of the first claw piece 7a and the second claw piece 7b By forming a concave portion 32 on one side of the facing surface of the collar portion 30 and forming a convex portion 33 on the other side, and closing the convex portion 33 in the concave portion 32, the outside of the component 5 can be gripped. And the inner side which is the opposite surface side of each of the first claw piece 7a and the second claw piece 7b. An outer flange portion 31 projecting toward the outer peripheral surface 34 on the opposite side of the portion 30 is formed, the gripping claw 7 is closed, and the convex portion 33 is inserted into the concave portion 32 on the inner jaw portion 30 side to hold the gripping claw 7. The gripping claw 7 is inserted into the hole of the component by reducing the outer dimension of the tip of the component, and then the gripping claw 7 is opened so that the inside of the component can be gripped, between the chuck opening / closing mechanism 20 and the gripping claw 7. In addition, an adapter 8 for connecting the chuck opening / closing mechanism 20 and the gripping claw 7 is interposed, and the shape of the fastening portion between the adapter 8 and the gripping claw 7 is different from that of the same chuck opening / closing mechanism 20 in the gripping. The position of the fastening hole 40 between the adapter 8 and the gripping claw 7 is unified so that the claw 7 can be attached, or the gripping claw 7 of the same shape can be attached to different chuck opening / closing mechanisms 20. A plurality of different adapters 8 A fastening hole position 41 corresponding to the position of the fastening hole 41 provided in each of the chucks 20 is provided.

  The end effector 1 according to a second aspect of the present invention is the end effector 1 according to the first aspect, wherein an angle α formed by the major axis direction of the adapter 8 with respect to the axial direction C of the robot arm 4 and the adapter 8 with respect to the axial direction C of the robot arm 4. The shape formed by the adapter 8 and the gripping claws 7 in a side view is such that the angle β formed in the major axis direction of the gripping claws 7 fastened to is 25 ° or more and 35 ° or less. The compliance device 3 is formed and interposed between the gripping side plate 50 attached to the gripping mechanism 2, the arm side plate 51 attached to the tip of the robot arm 4, and the gripping side plate 50 and the arm side plate 51. An intermediate plate 52 is provided.

  The end effector 1 according to claim 3 is the end effector 1 according to claim 1, wherein a space 53 is provided in which the space between the arm side plate 51 and the intermediate plate 52 is fixed, and the grip side plate 50 and the intermediate plate 50 are intermediate. An end of a shaft 55 inserted between the plates 52 and inserted through a spring 54 that urges the gap between the gripping side plate 50 and the intermediate plate 52 in the expansion direction from the intermediate plate 52 side to the space portion 53. A disc-shaped stop plate 56 is fixed to the tip of the shaft 55, and a disc-shaped fixed block is provided on the space 53 side of the intermediate plate 52 so as to face the stop plate 56. 57 is fixed, and when there is no load, the stopper plate 56 abuts against the fixed block 57 by the urging force of the spring 54 so that the gap between the grip side plate 50 and the intermediate plate 52 is increased. When loaded by an external force P that is expanded to the maximum and the gripping mechanism 2 collides, the spring 54 contracts and the tip of the shaft 55 protrudes into the space 53, and the grip side plate 50 and the intermediate plate 52. When the load P is reduced and the load P is impacted and the load is changed to no load, the stopper plate 56 fixed to the tip of the shaft 55 is stopped by the fixed block 57 by the extension of the spring 54. Thus, the distance between the grip-side plate 50 and the intermediate plate 52 is restored to a no-load state.

  The end effector 1 according to claim 1 is gripped when the gripping claw 7 is to be inserted into the hole of the component 5, for example, by forming a round shape on the outer peripheral surface 34 of the gripping claw 7. When the tip of the claw 7 comes into contact with the peripheral edge of the hole of the component 5, if the round is not formed, it remains in contact with the edge of the hole and is not inserted into the hole, but the round is formed. If the compliance device is mounted, the rounding portion slides around the periphery and the tip of the gripping claw 7 can be inserted into the hole without stopping a series of movements of the robot. Thereby, the occurrence frequency of chocolate stops in the robot 11 can be reduced.

  As shown in FIGS. 3 to 9, the gripping claw 7 is formed with a tapered shape toward the distal end portion of the gripping claw 7, and the opposing surfaces of the first claw piece 7 a and the second claw piece 7 b at the distal end portion are formed. The outer peripheral surface 34 except for forms a substantially hemispherical shape, forms a concave portion 32 on one side of the opposing surface of the inner collar portion 30 of the first claw piece 7a and the second claw piece 7b, and a convex portion 33 on the other side. When the gripping claw 7 is closed, the size can be reduced, and the gripping claw 7 can be inserted into the small hole portion of the component 5 as well. In addition, when the tip of the gripping claw 7 is displaced from the small hole portion of the component 5, if the tip of the gripping claw is large, the robot stops a little by the impact when contacting the vicinity of the peripheral edge of the hole. Since the tip of the gripping claw 7 can be reduced in size, the tip of the gripping claw 7 can be easily inserted into the hole of the component 5.

  As shown in FIGS. 3 to 9, by forming the inner collar part 30 and the outer collar part 31 at the tip of the gripping claw 7, the peripheral part of the hole of the component 5 can be grasped as shown in FIG. As shown in FIG. 11, the outside of the component 5 can be sandwiched and held. For this reason, even if the postures of the parts 5 stacked in the parts box 6 are different, the gripping claws 7 having the same shape can be held.

  An adapter 8 is interposed between the gripping claw 7 and a chuck opening / closing mechanism 20 that opens and closes the gripping claw 7. Since the gripping claws 7 have different gripping methods and shapes of gripping portions depending on the parts 5, the gripping claws 7 are provided with various shapes, and the chuck opening / closing mechanism 20 also has an interval for opening / closing the gripping claws 7 according to the shape of the parts. Since it is necessary to change the opening / closing force, various different forms of the chuck opening / closing mechanism 20 are provided. At this time, if the fastening method between the gripping claw 7 and the chuck opening / closing mechanism 20 differs depending on the shape of the gripping claw 7 or the chuck opening / closing mechanism 20, a plurality of forms of the chuck opening / closing mechanism 20 are provided for a certain kind of gripping claw 7. The position of the fastening hole 40 between the adapter 8 and the gripping claws 7 may be unified or different so that the gripping claws 7 having different shapes can be attached to the same chuck opening / closing mechanism 20. Fastening hole positions 41 corresponding to the positions of fastening holes 41 provided in the plurality of different chucks 20 on the adapter 8 so that the gripping claws 7 of the same shape can be attached to the chuck opening / closing mechanism 20. By providing, it is possible to greatly reduce the number of manufactured gripping claws 7 and chuck opening / closing mechanisms 20. In particular, since the gripping claw 7 is expensive to manufacture, it is possible to reduce the cost by using the adapter 8 to share the mounting form of the gripping claw 7.

  The end effector 1 according to claim 2 is shown in FIG. 25 when the shape of the gripping claw 7 is straight when the gripping claw 7 must be brought close to the component 5 from a position close to the frame of the component box 6. When the component 5 is stored in the corner of the component box 6 as shown in b), the end effector 1 interferes with the frame of the component box 6 so that the gripping claw 7 cannot be brought close to the component 5. However, in the case of the end effector 1 of the present invention as shown in FIGS. 21 to 23, even if the component 5 is stored in the corner of the component box 6, FIG. ), The gripping claw 7 or the robot 11 can grip the component 5 without interfering with the frame of the component box 6.

  The end effector 1 according to claim 3 is configured so that the gripping mechanism 2 of the end effector 1 attached to, for example, the tip of the arm 4 of the robot 11 deviates from the target position and collides with the surface of the component 5. The gripping mechanism 2 can easily slide to reach the target gripping location, and the load applied to the end effector 1 and the robot 11 when the gripping mechanism 2 collides with the component box 6 can be reduced. It is difficult to damage the expensive gripping mechanism 2 that is more easily damaged than other parts.

It is explanatory drawing of the components pick-up system using the end effector of this invention. It is explanatory drawing when an end effector collides with components and external force is added. It is explanatory drawing of the shape of the chuck | zipper opening / closing mechanism and the part of a holding claw in the case of a form which a holding claw opens / closes in a sliding direction, Comprising: It is a perspective view of the said site | part when a chuck mechanism is open. It is explanatory drawing of the shape of the part of a chuck | zipper opening / closing mechanism and a holding claw in the form which a holding claw opens / closes in a sliding direction, Comprising: It is a perspective view of the said site | part when a chuck mechanism is closed. It is explanatory drawing of the shape of the part of a chuck | zipper opening / closing mechanism and a holding claw in the form which a holding claw opens / closes in a sliding direction, Comprising: It is a front view of the said site | part. It is explanatory drawing of the form of the part of a chuck | zipper opening / closing mechanism and a holding claw in the form which a holding claw opens / closes in a sliding direction, Comprising: It is a rear view of the said site | part. It is explanatory drawing of the shape of the part of a chuck | zipper opening / closing mechanism and a holding claw in the form which a holding claw opens / closes in a sliding direction, Comprising: It is the right view or the left view of the said site | part. It is explanatory drawing of the shape of the front-end | tip part of a holding nail, (a) is a figure which shows the form at the time of the holding nail in the bottom view of a holding nail, (b) is the bottom view of a holding nail when the holding nail is closed It is a figure which shows a form, (c) is the figure which showed the state which the holding nail | claw in the rear view of the holding nail contact | abutted to corner | angular parts, such as components. It is explanatory drawing which shows the form which closed the holding nail | claw from the rear view of FIG. It is explanatory drawing in the case of gripping the edge part of a hole part, (a) is the figure which showed the state which inserted the nail | claw in the hole part of a component, (b) is the hole part of a component by opening a grip claw It is the figure which showed the state which hold | gripped the edge part. It is explanatory drawing at the time of holding | gripping across the external part of a component, (a) is the figure which showed the state which made the grip nail approach the outside of a component, (b) is the external shape of a component with a grip nail closed It is the figure which showed the state hold | gripped on both sides of FIG. It is explanatory drawing of the shape of the chuck | zipper opening / closing mechanism and the part of a holding claw in the case of the form which a holding claw opens / closes in a turning direction, Comprising: It is a perspective view of the said site | part when a chuck mechanism is open. It is explanatory drawing of the shape of the part of a chuck | zipper opening / closing mechanism and a holding claw in the form which a holding claw opens / closes in a turning direction, Comprising: It is a perspective view of the said site | part when a chuck mechanism is closed. It is explanatory drawing of the shape of the part of a chuck | zipper opening / closing mechanism and a holding claw in the form which a holding claw opens / closes in a turning direction, Comprising: It is a front view of the said site | part. It is explanatory drawing of the form of the part of a chuck | zipper opening / closing mechanism and a holding claw in the form which a holding claw opens / closes in a sliding direction, Comprising: It is a rear view of the said site | part. It is explanatory drawing of the shape of the part of a chuck | zipper opening / closing mechanism and a holding claw in the form which a holding claw opens / closes in a sliding direction, Comprising: It is the right view or the left view of the said site | part. It is explanatory drawing which shows the form which closed the holding nail | claw from the front view of FIG. It is explanatory drawing in the case of gripping the edge part of a hole part, (a) is the figure which showed the state which inserted the nail | claw in the hole part of a component, (b) is the hole part of a component by opening a grip claw It is the figure which showed the state which hold | gripped the edge part. It is explanatory drawing at the time of holding | griping components, (a) is the figure which showed the state which made the grip nail approach to components, (b) shows the state which hold | gripped the component with the grip nail closed. It is a figure. It is explanatory drawing of the shape of the chuck | zipper opening / closing mechanism and the part of a holding claw in the form which a holding claw opens / closes in a sliding direction, Comprising: (a) is a perspective view of the said part when a chuck mechanism is closed, (b ) Is a perspective view of the portion when the chuck mechanism is open. It is a perspective view which shows the form which opened the holding nail in the site | part of the adapter and the holding nail as described in Claim 2. It is a perspective view which shows the form which closed the holding nail in the site | part of the adapter and holding nail as described in Claim 2. It is a figure explaining the form of the site | part of the adapter described in Claim 2, and the holding nail | claw. It is the figure which showed the state which is going to hold | grip the components accommodated in the corner | angular part of the component box with the adapter and holding nail | claw of Claim 2. The figure which showed the state which is going to hold | grip the components accommodated in the corner of a parts box, and (a) showed the case of the form which bent the holding nail in the direction perpendicular to the major axis direction of a compliance device. FIG. 5B is a diagram showing a case where a gripping claw is attached in the same direction as the long axis direction of the compliance device. It is the figure which showed the state which is going to hold | grip the component accommodated in the corner of a component box, (a) tries to hold | grip the component accommodated in the corner of the component box with the adapter and the gripping claw of Claim 2. It is the figure which showed the state, (b) is the figure which showed the case of the form which bent the holding nail | claw in the orthogonal | vertical direction with respect to the major axis direction of a compliance device. It is a perspective view of the no-load state of the compliance device of the present invention. It is longitudinal cross-sectional explanatory drawing of the no-load state of the compliance device in the BB cross section of FIG. It is explanatory drawing which shows a change when the external force of a reduction direction is added to the compliance device of FIG.

  As shown in FIG. 1, for example, the end effector 1 according to the present invention is used in a component pick-up system 10 including an end effector 1, a robot 11, an image sensor 12, a robot control unit 13, and a component recognition unit 14 based on an image. The The end effector 1 includes a compliance device 3 and a gripping mechanism 2. The component pick-up system 10 is installed in a production line such as an automobile manufacturing factory or a semiconductor manufacturing factory, and a robot 11 having an end effector 1 having a compliance device 3 and a gripping mechanism 2 mounted on the tip of an arm 4 is attached to a component box 6. A large number of components 5 stored in a stacked state are gripped one by one by the end effector 1 and taken out and conveyed to the next process.

  As shown in FIG. 1 or FIG. 2, the end effector 1 includes a gripping mechanism 2 for gripping the components 5 housed in the component box 6 one by one and a compliance device 3 having compliance, and the compliance device 3 side. Attach to the robot arm tip. Due to the compliance of the end effector 1, the gripping mechanism 2 is less likely to be damaged when the gripping mechanism 2 collides with the component box 6, the impact on the robot 11 is reduced, and the robot 11 is prevented from being stopped. Alternatively, when the gripping claw 7 of the gripping mechanism 2 is slightly displaced from the gripped portion of the component 5 and comes into contact with the component 5, the gripping claw 7 assists to easily reach the gripped portion while sliding on the surface of the component 5. be able to.

  As shown in FIGS. 5 to 7 and FIGS. 14 to 16, the gripping mechanism 2 includes a chuck arm 21 including a pair of first and second arms 21 a and 21 b that opens and closes. And a chuck opening / closing mechanism 20 including a drive cylinder 22 that opens and closes the chuck arm 21. Further, on the tip side of the chuck arm 21, a first claw piece 7 a interlocked with the operation of the first arm 21 a, which opens and closes mutually by the operation of the drive cylinder 22 and grips the component 5, and A pair of gripping claws 7 including a second claw piece 7b interlocked with the operation of the second arm 21b is provided.

As shown in FIGS. 3, 4, 12, and 13, the first claw piece 7 a and the second claw piece 7 b of the pair of gripping claws 7 taper from the attachment portion of the chuck arm 21 toward the tip portion. In addition to forming a shape, the outer peripheral surface 34 other than the opposing surfaces of the first claw piece 7a and the second claw piece 7b at the tip portion forms a substantially hemispherical shape, and FIG. 5, FIG. 14, FIG. As shown to a), the lower end part of the opposing surface of the said 1st nail | claw piece 7a and the 2nd nail | claw piece 7b is protruded in the opposing side, respectively, and the inner collar part 30 is formed, and said 1st claw piece 7a and a 2nd nail | claw A concave portion 32 is formed on one side of the facing surface of the inner flange portion 30 of the piece 7b, and a convex portion 33 is formed on the other side. And as shown in FIG.8 (b), FIG.9 or FIG.17, the size of the front-end | tip part of the holding nail | claw 7 can be made small by closing in the direction which inserts the said convex part 33 in the said recessed part 32, Thereby, as shown to Fig.10 (a) and FIG.18 (a), the front-end | tip part of the holding nail | claw 7 can be inserted in the small hole part of the component 5. FIG.

Further, as shown in FIGS. 11 (a) and 19 (a), the gripping claw 7 is brought close to the outside of the component 5 in the open state, and then gripped as shown in FIGS. 11 (b) and 19 (b). The claw 7 can be closed and the inner wall portion of the cylindrical part of the component 5 can be placed on the inner jaw 30 of the gripping claw 7 and can be gripped by sandwiching both sides of the component 5.

Further, as shown in FIGS. 10 (a) and 18 (a), the gripping claw 7 is inserted into the hole of the component 5 in the closed state, and thereafter, as shown in FIGS. 10 (b) and 18 (b). It is also possible to place the bottom surface of the component 5 on the outer jaw 31 of the gripping claw 7 by opening the gripping claw 7 and press the outside of the gripping portion 7 against the inner peripheral wall of the hole to grip the component.

By forming the outer peripheral surface 34 at the tip of the first claw piece 7a and the second claw piece 7b into a substantially hemispherical shape, the first claw piece 7a or the second claw piece 7b becomes as shown in FIG. As shown, the first claw piece 7a or the second claw piece 7b can be slid easily from the corner of the part 5 when abutting against the corner of the part 5, and the first claw piece 7a or the second claw piece can be made. 7b becomes easy to insert into the hole of the component 5.

  The material of the first claw piece 7a and the second claw piece 7b usually needs to be repeatedly held and released from the metal part 5, and may be any material having wear resistance.

As shown in FIGS. 3, 5, 12, and 14, an adapter 8 that connects the chuck opening / closing mechanism 20 and the gripping claws 7 is interposed between the chuck opening / closing mechanism 20 and the gripping claws 7. The fastening portion between the adapter 8 and the gripping claw 7 is used for fastening the adapter 8 and the gripping claw 7 so that the gripping claws 7 having different shapes can be attached to the same chuck opening / closing mechanism 20. Fastening holes 41 provided in the plurality of different chucks 20 in the adapter 8 so that the positions of the holes 40 are unified or the gripping claws 7 of the same shape can be attached to different chuck opening / closing mechanisms 20. A fastening hole position 41 corresponding to this position is provided. Thereby, the gripping claws 7 having different shapes can be attached to the same adapter 8. On the other hand, as shown in FIGS. 12 and 20, the same gripping claw 7 can be attached to an adapter 8 having a different shape. Thereby, the number of types of adapters 8 and the number of types of grip claws 7 can be reduced.

The chuck opening / closing mechanism 20 is provided with a drive cylinder 22 that opens and closes the first claw piece 7a and the second claw piece 7b. As shown in FIGS. 12 and 14, the opening and closing modes include a mode in which the tips of the first claw piece 7 a and the second claw piece 7 b are opened and closed with an arcuate locus, and a shape shown in FIGS. 3 and 5. The first claw piece 7a and the second claw piece 7b can be opened and closed by sliding them horizontally.

Further, as shown in FIGS. 21 to 23, the angle α formed by the major axis direction of the adapter 8 with respect to the axial direction C of the robot arm 4 and the grip fastened to the adapter 8 with respect to the axial direction C of the robot arm 4. The shape formed by the adapter 8 and the gripping claw 7 in a side view is formed in a dogleg shape so that the angle β formed by the major axis direction of the claw 7 is 25 degrees or more and 35 degrees or less.

  Accordingly, as shown in FIGS. 24 and 26 (a), in the case of the end effector 1 of the present invention, the gripping claws 7 are attached to the component box 6 even when the component 5 is stored in the corner of the component box 6. The part 5 can be gripped without the robot 11 stopping without interfering with the frame.

As a comparative example, when the gripping claws 7 are arranged in the direction perpendicular to the axial direction of the compliance device 3 as shown in FIG. 25A and FIG. In the case shown in FIG. 25A, the end effector 1 can be gripped by interfering with the component box 6 in the case shown in FIG. Therefore, the trouble that the robot 11 becomes a chocolate stop occurs.

As a comparative example, when the gripping claws 7 are arranged in the same direction with respect to the axial direction C of the robot arm 4 as shown in FIG. 25 (b), the gripping claws 7 as shown in FIG. 25 (b). Cannot interfere with the component box 6 and grip the component 5.

  As shown in FIGS. 27 to 29, the compliance device 3 is provided with a space portion 53 in which a space between the arm side plate 51 and the intermediate plate 52 is fixed, and the grip side plate 50 and the intermediate plate 52. An end of a shaft 55 inserted through a spring 54 interposed between the holding side plate 50 and the intermediate plate 52 and biased in the expansion direction is inserted into and removed from the space 53 from the intermediate plate 52 side. A disc-shaped stop plate 56 is fixed to the tip of the shaft 55, and a disc-shaped fixing block 57 is provided on the space 53 side of the intermediate plate 52 so as to face the stop plate 56. Secure. In order to prevent the bearing 60 on the gripping plate 50 side from moving in the axial direction of the shaft 55, the stopper 61 is brought into close contact with the bearing 60 and fitted to the shaft 55.

  When no load is applied, as shown in FIG. 28, the biasing force of the spring 54 causes the stopper plate 56 to abut against the fixed block 57 and the distance between the gripping side plate 50 and the intermediate plate 52 is maximized. When loaded by an external force P applied when the gripping mechanism 2 collides, the spring 54 contracts and the tip of the shaft 55 projects into the space 53 as shown in FIG. 29, so that the gripping side plate 50 and the intermediate plate When the interval of 52 is reduced and the impact of the load P is received and the load is changed to no load, as shown in FIG. 28, the stopper plate 56 fixed to the tip of the shaft 55 is expanded by the extension of the spring 54. It is stopped by the fixing block 57, and the interval between the gripping side plate 50 and the intermediate plate 52 is restored to the unloaded state.

  A bearing 60 is fitted into a connecting portion between the shaft 55 and the gripping side plate 50 and the intermediate plate 52. For example, as shown in FIGS. 28 and 29, bearings 60 are respectively fitted at positions facing the grip side plate 50 and the intermediate plate 52. Then, an end portion of the shaft 55 is connected to the bearing 60 on the gripping side plate 50 side that is fitted in the facing position, and the shaft 55 is inserted into the bearing 60 on the intermediate plate 52 side. The bearing 60 may be any of a ball bearing, a roller bearing, and a spherical plain bearing. In the case of a ball bearing or a roller bearing, the shaft 55 can be caused to slide in the vertical direction with respect to the intermediate plate 52, and thus the spherical surface. In the case of a sliding bearing, the shaft 55 can be slid in the vertical direction with respect to the intermediate plate 52, and can be oscillated or tilted with respect to the intermediate plate and the gripping side plate 50.

  In addition, as shown in FIG. 27, the compliance device 3 includes the shaft 55 and the bearing 60 as a set, and at least three locations between the grip side plate 50 and the intermediate plate 52. By providing three or more locations, the grip-side plate 50 is three-dimensionally, for example, in the case of a spherical plain bearing, depending on the position, size and orientation of the applied load with reference to the plate attached to the arm 4 side of the robot 11. It is possible to change the tilt and to change the torsion.

DESCRIPTION OF SYMBOLS 1 End effector 2 Grasp mechanism 3 Compliance device 4 Arm 5 Parts 6 Parts box 7 Grasp claw 7a First claw piece 7b Second claw piece 8 Adapter 10 Parts extraction system 11 Robot 12 Image sensor 13 Robot controller 14 Parts recognition means 20 Chuck Opening / closing mechanism 21 Chuck arm 21a First arm 21b Second arm 22 Drive cylinder 30 Inner jaw portion 31 Outer jaw portion 32 Recessed portion 33 Convex portion 34 Outer peripheral surface 40 Fastening hole 41 Fastening hole 50 Gripping side plate 51 Arm side plate 52 Intermediate Plate 53 Space portion 54 Spring 55 Shaft 56 Stop plate 57 Fixed block 60 Bearing 61 Stopper 70 Holding claw 71 Holding claw C Axial direction P External force α angle β angle

Claims (3)

An end effector that is attached to the tip of a robot arm for picking a component,
The end effector includes a gripping mechanism that grips a component, and a compliance device that is attached to the tip of the robot arm and exhibits compliance when an external force is applied to the gripping mechanism,
The gripping mechanism includes a chuck arm including a pair of first and second arms that are opened and closed, a chuck opening and closing mechanism that includes a drive cylinder that is connected to the chuck arm and opens and closes the chuck arm, and the drive A pair of grips composed of a first claw piece interlocked with the operation of the first arm and a second claw piece interlocked with the operation of the second arm, which grips a part by opening and closing each other by the operation of the cylinder. Nail, and
The first claw piece and the second claw piece of the pair of gripping claws form a tapered shape from the attachment portion of the chuck arm toward the tip portion, and the first claw piece and the second claw piece at the tip portion. The outer peripheral surface other than the opposing surface forms a substantially hemispherical shape,
The lower end of the opposing surface of the first claw piece and the second claw piece is protruded to the opposing side to form an inner collar part, and one of the opposing surfaces of the inner hook part of the first and second claw pieces By forming a concave portion on the side and forming a convex portion on the other side, and closing in the direction in which the convex portion is inserted into the concave portion, the outside of the component can be gripped,
Forming an outer flange projecting on the outer peripheral surface opposite to the inner jaw, which is the opposing surface side of each of the first and second claws, and closing the gripping claws to the inner jaw side The convex portion is inserted into the concave portion to reduce the outer dimension of the tip of the gripping claw, and the gripping claw is inserted into the hole of the component, and then the gripping claw is opened so that the inside of the component can be gripped.
An adapter for connecting the chuck opening / closing mechanism and the gripping claw is interposed between the chuck opening / closing mechanism and the gripping claw, and the form of the fastening portion between the adapter and the gripping claw is set to the same chuck opening / closing mechanism. The positions of the fastening holes between the adapter and the gripping claws are unified so that the gripping claws of different shapes can be attached, or the gripping claws of the same shape can be attached to different chuck opening / closing mechanisms. An end effector characterized in that a position of a fastening hole corresponding to a position of a fastening hole provided in each of a plurality of different chucks is provided in an adapter. The angle formed by the long axis direction of the adapter with respect to the axial direction of the robot arm and the angle formed by the long axis direction of the gripping claws fastened to the adapter with respect to the axial direction of the robot arm are both 25 degrees or more and 35 degrees or less. As shown, the shape formed by the adapter and the gripping claw in a side view forms a U-shape,
The compliance device includes a gripping side plate attached to the gripping mechanism, an arm side plate attached to the tip of the robot arm, and an intermediate plate interposed between the gripping side plate and the arm side plate. The end effector according to claim 1. A space is provided in which the space between the arm side plate and the intermediate plate is fixed, and is interposed between the grip side plate and the intermediate plate, and the space between the grip side plate and the intermediate plate is set in the expansion direction. The shaft tip inserted through the biased spring can be taken into and out of the space from the intermediate plate side,
A disc-shaped stop plate is fixed to the tip of the shaft, and a disc-shaped fixing block is fixed to the space portion side of the intermediate plate so as to face the stop plate,
When no load is applied, the stopper plate abuts on the fixed block by the biasing force of the spring, and the gap between the grip side plate and the intermediate plate is expanded to the maximum.
When a load is applied due to an external force applied when the gripping mechanism collides, the spring contracts and the shaft tip projects into the space, and the distance between the gripping side plate and the intermediate plate decreases to receive the impact of the load. When the load is no longer loaded, the stopper plate fixed to the tip of the shaft by the extension of the spring is stopped by the fixed block, so that the gap between the gripping side plate and the intermediate plate The end effector according to claim 1, wherein the end effector is restored to a state.

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