This application is based upon and claims the benefit of priority from the corresponding Japanese Patent Application No. 2019-190950 filed on Oct. 18, 2019, the entire contents of which are incorporated herein by reference.
The present disclosure relates to a gripping mechanism.
A typical automated assembling apparatus includes a chuck mechanism for gripping parts for transport purposes. The chuck mechanism is an electric gripping mechanism. In addition, a gripping mechanism using air suction or electric suction is known.
Typical gripping mechanisms utilize power, such as a pneumatic or electrical energy, and are therefore costly and prone to failure.
A gripping mechanism according to the present disclosure includes a gripping body and a frame body. The frame body accommodates the gripping body and includes a plate-shaped part that grips a grasped part of an object. The gripping body has a flat surface that grips the grasped part. The gripping mechanism grips the grasped part of the object between the flat surface of the gripping body and an inner surface of the plate-shaped part of the frame body by an action of gravity operating on the gripping body.
First, referring to
As illustrated in
The gripping mechanism 3 grips the first component 4. The second component 5 is positioned on a positioning mechanism 10.
The positional deviation correction device 2 corrects a positional deviation of the first component 4 grasped by the gripping mechanism 3 with respect to the second component 5. Specifically, the positional deviation correction device 2 detects the direction of a force operating on the first component 4, when the first component 4 is fitted to the second component 5, and corrects the positional deviation of the first component 4 according to the direction of the force.
The robot 1 moves the gripping mechanism 3 relatively to the first component 4 and moves the gripping mechanism 3 relatively to the second component 5. Specifically, the robot 1 moves the gripping mechanism 3 to the storage location of the first component 4, causes the gripping mechanism 3 to grip the first component 4, and then moves the first component 4 together with the gripping mechanism 3 to the position directly above the second component 5. Thereafter, the robot 1 moves the first component 4 together with the gripping mechanism 3 in the positive direction of the Z-axis, thereby fitting the first component 4 to the second component 5. After the fitting is achieved, the robot 1 releases a gripping of the gripping mechanism 3 with respect to the first component 4 and moves the gripping mechanism 3 in the negative direction of the Z axis.
Next, referring to
As illustrated in
The gripping roller 32 includes a columnar core part 321 and a covering part 322 covering a peripheral surface of the core part 321. For example, the core part 321 is made of metal such as iron, and the covering part 322 is made of an elastic body such as a polyacetal resin. The density of the core part 321 is higher than the density of the covering part 322. The covering part 322 is compressively deformable. The friction coefficient of the peripheral surface of the covering part 322 is larger than the friction coefficient of the peripheral surface of the core part 321.
The gripping roller 32 has a radius R that extends from the central axis of the core part 321 to the peripheral surface.
The back plate 311 is a rectangular plate extending along the ZX plane. The top plate 312 is a rectangular plate extending along the XY plane starting from the upper edge of the back plate 311. The upper front plate 313 is a rectangular plate that starts from the front edge of the top plate 312 and extends obliquely downward in the direction away from the back plate 311. The lower front plate 314 is a rectangular plate that starts from the lower edge of the upper front plate 313 and extends obliquely downward toward the back plate 311.
An opening 315 is formed between the back plate 311 and the lower front plate 314. The width of the opening 315 in the Y direction is smaller than the diameter 2R of the gripping roller 32. Therefore, the gripping roller 32 does not fall through the opening 315. The back plate 311 and the lower front plate 314 support the weight of the gripping roller 32. The opening 315 accepts insertion of a grasped part 42 of a component body 41 (
The back plate 311, the top plate 312, the upper front plate 313, and the lower front plate 314 form substantially pentagonal openings on the left and right side surfaces of the holder 31. The left and right side plates 316 are installed so as to close these openings. In addition, the side plates 316 are openable and closable, which allows the gripping roller 32 to be easily taken in and out of the gripping mechanism 30.
At least one of the side plates 316 has, at the position close to the back plate 311, a cutout part 317 through which the grasped part 42 (
Next, referring to
As illustrated in
In the gripping mechanism 30 of the related art, a height L1 from the point at which the end surface of the grasped part 42 is connected to one of the main surfaces of the component body 41 to a vertex of the grasped part 42 must be larger (higher) than the radius R of the gripping roller 32.
The gripping mechanism 30 grips the grasped part 42 of the first component 4 between the outer surface of the gripping roller 32 and the inner surface of the holder 31 by the action of the gravity operating on the gripping roller 32. Specifically, in the gripping state illustrated in
The operation of the assembling apparatus 100 will be described with reference to
In the first step, as illustrated in
As illustrated in
In the second step, the robot 1 moves the gripping mechanism 30 in the negative direction of the Z axis while maintaining the gripping state. As illustrated in
In the third step, the robot 1 moves the gripping mechanism 30 in the positive direction of the Z-axis. As a result, the first component 4 is fitted to the second component 5. In the case where the grasped part 42 slides and moves between the outer surface of the covering part 322 and the inner surface of the back plate 311 at the time of fitting, an auxiliary means for pressing the first component 4 in the positive direction of the Z-axis may be added. The gripping state illustrated
In the fourth step, the robot 1 moves the gripping mechanism 30 in the positive direction of the X axis (or the negative direction of the X axis). The grasped part 42 passes between the outer surface of the covering part 322 and the inner surface of the back plate 311, and further passes through the cutout part 317. As a result, the gripping of the first component 4 by the gripping mechanism 30 is released. The first component 4 remains fitted to the second component 5.
In the fifth step, the robot 1 returns the gripping mechanism 30 to the original position in preparation for the next operation while moving the gripping mechanism 30 in the negative direction of the Z axis.
Note that, in order to prevent the first component 4 from falling in the gripping state illustrated in
A gripping mechanism 3 according to a first embodiment of the present disclosure will be described with reference to
A positional deviation correction device 2 according to the first embodiment illustrated in
As illustrated in
The frame body 33 has a support part 334 for supporting the weight of the gripping body 34 together with the plate-shaped part 331, and an opening 337 for accepting the insertion of the object 43 is formed between the plate-shaped part 331 and the support part 334.
The frame body 33 of the gripping mechanism 3 accommodates the gripping body 34. The frame body 33 includes the plate-shaped part 331, a top plate 332, an upper front plate 333, and the support part 334. The frame body 33 may be made of, for example, a light metal such as aluminum. These matters can be applied in all of the present disclosure.
The plate-shaped part 331 is a rectangular planar plate extending along the ZX plane. The top plate 332 is a rectangular plate extending along the XY plane starting from the upper edge of the plate-shaped part 331. The upper front plate 333 is a rectangular plate that starts from the front edge of the top plate 332 and extends obliquely downward in the direction away from the plate-shaped part 331. The upper front plate 333 may be a rectangular plate extending vertically downward from the plate-shaped part 331 with the front edge of the top plate 332 as the starting end. The support part 334 is a rectangular plate extending obliquely downward from the lower edge of the upper front plate 333 toward the plate-shaped part 331.
The opening 337 is formed between the lower end of the plate-shaped part 331 of the frame body 33 and the lower end of the support part 334. The opening 337 accepts insertion of the grasped part 44 of the object 43.
The gripping body 34 has the flat surface 341 on the side facing the inner surface 335 of the plate-shaped part 331 of the frame body 33. The gripping body 34 sandwiches the grasped part 44 of the object 43 between the gripping body 34 in itself and the plate-shaped part 331 of the frame body 33. That is, the grasped part 44 of the object 43 is inserted between the flat surface 341 of the gripping body 34 and the inner surface 335 of the plate-shaped part 331 of the frame body 33, and the grasped part 44 of the object 43 is grasped by the flat surface 341 and the inner surface 335. Thus, the object 43 is grasped by the gripping mechanism 3.
A surface of the gripping body 34 other than the flat surface 341 may be a flat surface or a curved surface. The gripping body 34 may be a polyhedron. An inclined surface 343 on the opposite side of the flat surface 341 of the gripping body 34 faces an inner surface 336 of the support part 334 of the frame body 33. The inclined surface 343 may be a flat surface or a curved surface. However, when the inner surface 336 is a flat surface, the inclined surface 343 is preferably also a flat surface. When the inner surface 336 is a curved surface, the inclined surface 343 is preferably a curved surface having the same curvature as the inner surface 336 has. These matters can be applied in all of the present disclosure.
That is, it is preferable that the flat surface 341 of the gripping body 34 be in close contact with the inner surface 335 of the plate-shaped part 331 of the frame body 33 by the action of gravity operating on the gripping body 34. In addition, it is preferable that the inclined surface 343 of the gripping body 34 be in close contact with the inner surface 336 of the support part 334 of the frame body 33 by the action of the gravity operating on the gripping body 34.
The gripping body 34 further has a lower surface 344. In a connecting part between the lower surface 344 and the flat surface 341, a taper 342 may be provided. The taper 342 is an inclined surface so formed as to extend from the lower surface 344 toward the flat surface 341. Since the gripping body 34 has the taper 342, the object 43 is easily inserted between the gripping body 34 and the plate-shaped part 331 of the frame body 33.
The object 43 has the grasped part 44 which protrudes from an upper surface 45 of the object 43 and is grasped by the flat surface 341 of the gripping body 34 and the plate-shaped part 331 of the frame body 33.
The object 43 has, for example, a substantially rectangular-parallelepipedic shape. The grasped part 44 protrudes from the upper surface 45 of the object 43 facing the gripping mechanism 3 so that the grasped part 44 may easily be grasped by the gripping mechanism 3. The grasped part 44 may be formed integrally with the object 43. The grasped part 44 may be so formed as to connect with the upper surface 45 of the object 43.
A height L2 of the grasped part 44 may be a minimum height (distance) allowing the grasped part 44 to be sandwiched between (grasped by) the gripping body 34 and the plate-shaped part 331 of the frame body 33. The height L2 is lower (smaller) than the height L1 described with reference to
According to the present embodiment, since the grasped part 44 of the object 43 is grasped by the gripping body 34 and the frame body 33 by the action of gravity operating on the gripping body 34, the gripping mechanism 3 that is less likely to fail is provided. In addition, since the gripping body 34 has the flat surface 341 that grips the grasped part 44 of the object 43, the adhesion between the flat surface 341 of the gripping body 34 and the inner surface 335 of the plate-shaped part 331 of the frame body 33 is increased. Therefore, the gripping mechanism 3 efficiently grips the object 43, and the work efficiency of transporting the object 43 is improved.
Further, according to the present embodiment, the grasped part 44 of the object 43 is easily inserted into the frame body 33 through the opening 337. In addition, since the inclined surface 343 of the gripping body 34 is in close surface contact with the inner surface 336 of the support part 334 of the frame body 33 and the object 43 is brought into close surface contact with and sandwiched between the flat surface 341 of the gripping body 34 and the inner surface 335 of the plate-shaped part 331 of the frame body 33, the gripping mechanism 3 grips the object 43 more accurately.
Further, according to the present embodiment, since the object 43 has the grasped part 44, the frame body 33 easily grips the object 43 along with the gripping body 34. In addition, since the flat surface 341 of the gripping body 34 and the inner surface 335 of the plate-shaped part 331 of the frame body 33 are brought into close surface contact with the grasped part 44 of the object 43 so as to grip the grasped part 44, the height L2 of the grasped part 44 can be made lower (smaller) than in the case where the gripping body 34 is a cylindrical body or a spherical body, and the cost for manufacturing the grasped part 44 is reduced.
Next, the operation of the gripping mechanism 3 according to the first embodiment will be described with reference to
As illustrated in
The robot 1 of the assembling apparatus 100 (
As illustrated in
As illustrated in
Due to the action of gravity operating on the gripping body 34, the inner surface 336 of the support part 334 of the frame body 33 and the inclined surface 343 of the gripping body 34 are brought into close contact with each other, and the grasped part 44 of the object 43 is sandwiched between and grasped by the inner surface 335 of the plate-shaped part 331 of the frame body 33 and the flat surface 341 of the gripping body 34.
Since the inner surface 335 and the flat surface 341 are parallel to each other, the grasped part 44 of the object 43 is sandwiched between the inner surface 335 and the flat surface 341 under a strong static friction force on both side surfaces of the grasped part 44. Therefore, the height (dimension) L2 of the grasped part 44 is made low (small) as far as such a static friction force as preventing the object 43 from falling from the gripping mechanism 3 is generated on the grasped part 44.
Next, the configuration of the gripping body 34 of a gripping mechanism 3 according to a second embodiment will be described with reference to
The gripping mechanism 3 according to the second embodiment includes a rotating body 35 or a rotating body 36 in addition to the frame body 33 and the gripping body 34. The gripping body 34 has a case 351 or a case 361 in the inclined surface 343 facing the support part 334, and the rotating body 35 or the rotating body 36 can be rotatably mounted in the case 351 or the case 361.
That is, as illustrated in
The case 351 and the case 361 each have an opening in the inclined surface 343. A part of each of the rotating body 35 and the rotating body 36 is projected from the opening in the inclined surface 343. The rotating bodies 35 and 36 may each be a spherical body such as a ball or a cylindrical body such as a roller. These matters can be applied in all of the present disclosure.
Since the peripheral surface of the rotating body 35 is formed of an elastic body, the rotating body 35 can be mounted in the case 351, accommodated in the case 351, and can be removed from the case 351.
Since the peripheral surface of the rotating body 36 is formed of an elastic body, the rotating body 36 can be mounted in the case 361, accommodated in the case 361, and can be removed from the case 361.
As illustrated in
As illustrated in
As illustrated in
Since the inner surface 336 of the support part 334 of the frame body 33 and the peripheral surfaces of the rotating body 35 and the rotating body 36 are brought into close contact with each other by the action of gravity operating on the gripping body 34, the rotating body 35 and the rotating body 36 urge the gripping body 34. Accordingly, the grasped part 44 of the object 43 is sandwiched between and grasped by the inner surface 335 of the plate-shaped part 331 of the frame body 33 and the flat surface 341 of the gripping body 34.
According to the present embodiment, since the rotating body 35 and the rotating body 36 mounted on the gripping body 34 reduce the resistance between the support part 334 of the frame body 33 and the inclined surface 343 of the gripping body 34, the gripping body 34 easily falls after the grasped part 44 of the object 43 is inserted into the frame body 33 through the opening 337 of the frame body 33, and the object 43 is sandwiched between and grasped by the frame body 33 and the gripping body 34.
Next, the configuration and the operation of the gripping body 34 of a gripping mechanism 3 according to a third embodiment will be described with reference to
As illustrated in
According to the present embodiment, as illustrated in
Similarly to the second embodiment as illustrated in
Therefore, when the gripping body 34 is lifted in the direction C, the rotating body 35 or the rotating body 36 can rotate, and the friction between the inclined surface 343 of the gripping body 34 and the inner surface 336 of the support part 334 is reduced.
Further, as illustrated in
Therefore, a large static friction force is generated between the rotating body 35 and the rotating body 36 of the gripping body 34 and the inner surface 336 of the support part 334 of the frame body 33. As a result, the gripping body 34 is more difficult to push back in the vertically upward direction than the gripping body 34 according to the second embodiment, and the grasped part 44 of the object 43 is grasped by the gripping body 34 and the plate-shaped part 331 of the frame body 33 with a static friction force stronger than the static friction force in the second embodiment.
Next, the configuration of the gripping body 34 of a gripping mechanism 3 according to a fourth embodiment will be described with reference to
As illustrated in
The rotating body 37 presented as an example in the fourth embodiment has a larger radius than the rotating body 35 and the rotating body 36 presented as an example in the second embodiment and the third embodiment.
The case 371 has an opening in the inclined surface 343. A part of the rotating body 37 is projected from the opening in the inclined surface 343. The rotating body 37 may be a spherical body such as a ball or a cylindrical body such as a roller. These matters can be applied in all of the present disclosure.
Since the peripheral surface of the rotating body 37 is formed of an elastic body, the rotating body 37 can be mounted in the case 371, accommodated in the case 371, and can be removed from the case 371.
As illustrated in
As illustrated in
As illustrated in
Since the inner surface 336 of the support part 334 of the frame body 33 and the peripheral surface of the rotating body 37 are brought into close contact with each other by the action of the gravity operating on the gripping body 34, the rotating body 37 urges the gripping body 34. Accordingly, the grasped part 44 of the object 43 is sandwiched between and grasped by the inner surface 335 of the plate-shaped part 331 of the frame body 33 and the flat surface 341 of the gripping body 34.
According to the present embodiment, the rotating body 37 mounted on the gripping body 34 reduces the resistance between the support part 334 of the frame body 33 and the inclined surface 343 of the gripping body 34. Since the radius of the rotating body 37 is large as compared with the radii of the rotating body 35 and the rotating body 36 described in the second embodiment and the third embodiment, the contact area when the rotating body 37 is in close contact with the inner surface 336 of the support part 334 of the frame body 33 is large.
Therefore, after the grasped part 44 of the object 43 is inserted into the frame body 33 through the opening 337 of the frame body 33, the gripping body 34 easily falls, and the object 43 is sandwiched between and grasped by the frame body 33 and the gripping body 34 with a more suitably strong static friction force.
Next, the configuration and the operation of the gripping body 34 of a gripping mechanism 3 according to a fifth embodiment will be described with reference to
As illustrated in
According to the present embodiment, as illustrated in
Similarly to the fourth embodiment as illustrated in
Therefore, when the gripping body 34 is lifted in the direction C, the rotating body 37 can rotate, and the friction between the inclined surface 343 of the gripping body 34 and the inner surface 336 of the support part 334 is reduced.
Further, as illustrated in
Therefore, a large static friction force is generated between the rotating body 37 of the gripping body 34 and the inner surface 336 of the support part 334 of the frame body 33. As a result, the gripping body 34 is difficult to push back in the vertically upward direction, and the grasped part 44 of the object 43 is grasped by the gripping body 34 and the plate-shaped part 331 of the frame body 33 with a suitably strong static friction force.
Further, the contact area between the peripheral surface of the rotating body 37 and the inner surface 336 of the support part 334 of the frame body 33 is increased when the rotating body 37 having a larger radius according to the fifth embodiment is provided. Therefore, the grasped part 44 of the object 43 is more suitably grasped by the gripping body 34 and the plate-shaped part 331 of the frame body 33 with a strong static friction force than in the case where the rotating body 35 and the rotating body 36 each having a small radius are provided as in the third embodiment.
According to the configuration of each embodiment of the present disclosure, a low-cost gripping mechanism that is less likely to fail is realized.
Since the description of each embodiment of the present disclosure describes a preferable embodiment of the present disclosure, a variety of technically preferable limitations may be imposed, but the technical scope of the present disclosure is not limited to the described embodiments unless any statement specifying the present disclosure is made. That is, the constituent elements in the above embodiments may be appropriately replaced with existing constituent elements or the like, and diverse variations including combinations with other existing constituent elements are possible. The above description of the embodiments does not limit the content of the disclosure in the claims.
Number | Date | Country | Kind |
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2019-190950 | Oct 2019 | JP | national |