JPH042788Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a technology related to a robot hand.

[Conventional technology]

A robot has a hand attached to the tip of its arm, and is configured to grip an object with the swinging hand.

Prior art documents disclosing robot hands include, for example, Utility Model Application Publication No. 59-173591 and Japanese Patent Application Publication No. 1987-173591.
146789, JP-A-60-6378, JP-A-60-19621, JP-A-61-96631, JP-A-58-181593 or JP-A-58-181592.

By the way, when the robot's hand grasps items that are randomly placed rather than items that are arranged in a row, it is not necessary to grasp them mechanically.
Either negative pressure or magnetic attraction is used.

For example, if we consider the case of magnetic attraction, there are two ways to do this: you can simply attract the item magnetically, or you can use a hand shaped to match the shape of the item to attach the hand to the item. You can either align the item and then use magnetic force to attract it, but it is better to use the latter, that is, to use a hand that matches the shape of the item.

This is because, rather than simply attracting an item with magnetic force, it is better to use a hand that matches the shape of the item to increase the contact area between the item and the hand, and then use magnetic force to attract the item. This is because only a small amount of magnetic energy is required to lift an item, and the entire robot can therefore be made smaller.

As an example of a hand that matches the shape of the item,
The applicant previously proposed a hand as shown in FIG. FIG. 7 was filed by the present applicant on December 25, 1985 (therefore, it is currently unknown).

In Fig. 7, a main shaft 30 is attached to the tip of a robot arm (not shown) via a hand housing 2, and a main shaft 30 is fixed to the main shaft 30 and extends in parallel with a certain interval. Right support 47 and left support 48
There is. At the tips of the right support 47 and the left support 48, work pieces 61 and 62 for gripping the item 13 are slidable in the vertical direction with respect to the right support 47 and the left support 48 and rotated in the front and back directions. movably mounted. In addition, the right support 47 and the left support 48 have workpiece pads 6.
A drive means 54, ie an electromagnet, is attached to the drive means 54, ie, an electromagnet, for causing the objects 1, 62 to grip the article 13. Reference numeral 85 is a part that comes into contact with the item 13;
The shape matches the shape of 3.

According to such a hand, in addition to what was mentioned above (the entire robot can be made smaller by using a hand that matches the shape of the item), the workpiece supports 61 and 62 can be attached to the right support 47 and the left support 48. On the other hand, since it can be slid in the vertical direction and rotated in the front and back directions, it is suitable for gripping items that are placed at an angle.

[Problem that the invention attempts to solve]

However, even with the device shown in FIG. 7, there was a problem in that it was relatively difficult to grip an item placed at an angle.

This is due to the following reason. That is, as shown in FIG. 8 (in FIG. 8, 5 is the whole hand, 47 and 48 are the right support and left support, 30 is the main shaft, and 2 is the hand housing), it is placed with an inclination. When the hand 5 approaches the work piece 13 from diagonally above, the work pieces 61 and 6
2 hangs vertically downward, so when it reaches the item 13, the work pieces 61, 62 and the item 13 form an angle, so the work pieces 61, 62 align only with a part of the item 13. .

The present invention solves these problems of the conventional technology.

The technical problem of the present invention is to prevent the work piece from hanging vertically downward when the hand approaches the item placed at an angle from above. The aim is to make it possible to grip the object reliably.

[Means for solving problems]

In order to achieve this technical problem, the following measures are taken in the present invention.

That is, the robot hand according to the present invention consists of a main shaft attached to the tip of the robot arm, and a right support and a left support that are fixed to the main shaft and extend parallel to each other with a certain distance between them. In the robot hand, a workpiece for gripping an item is attached to the tips of the right support and the left support, and the contact surface of the workpiece to the item is shaped like the item. The right support and the left support are provided with claws extending toward the workpiece at the tips thereof, and the workpiece has a step that engages with the claw. A fitting part is provided, and the stepped part of the workpiece pad is configured to removably engage with the pawl from above, and when the pawl and the stepped part are engaged, The workpiece stopper is integrally connected to the right support and the left support, and when the claw and the stepped part are disengaged, the workpiece stopper is connected to the right support and the left support. can be slid in the vertical direction and rotated in the front-back direction,
Further, the right support and the left support are provided with driving means for causing the workpiece support to grip the article.

[Effect]

In the present invention, even when the hand approaches an item placed diagonally from above, the claws are aligned with the stepped part, so the workpiece rest can be attached to the right support and the left support. They are all one. Therefore, in the middle, the workpiece rest is parallel to the right support and the left support. Therefore, the work piece is perpendicular to the item even at the moment of contact with the item.

When the work piece abuts the item at right angles and receives a reaction force from the item, the work piece is lifted upward and the claws are removed from the stepped portion. For this reason,
The workpiece is rotated so that it is perfectly aligned with the item. Therefore, even if the item is placed at an angle, the workpiece support will be perfectly aligned with the item. Therefore, the item can be gripped reliably.

〔Example〕

FIG. 1 is a longitudinal sectional view of a robot hand according to an embodiment of the present invention.

In Fig. 1, 1 is the arm of the robot, and the arm 1 has a hand housing 2 attached to a bolt 3.
It is fixed by. Reference numeral 4 designates a knock pin for positioning the arm 1 and the hand housing 2.

A hand 5 is attached to the hand housing 2. Before explaining the hand 5, the overall structure of the robot to which the hand 5 of FIG. 1 is attached will be briefly explained based on FIG. 5.

FIG. 5 is a side view of a robot to which the hand of FIG. 1 is attached.

In FIG. 5, 10 indicates the entire robot, 1 is an arm of the robot, and 2 is a hand housing. The hand 5 in FIG. 1 is located at a portion designated by reference numeral 11.

12 is a first pallet containing many items 13. In the first pallet 12 there is an item 1
3 are not arranged in a row, but are stored randomly. The role of the robot 10 shown in FIG. 5 is to grasp these randomly stored items 13 one by one with the hand 5 and arrange them properly on a second pallet (not shown) or a belt conveyor (not shown). be. For this purpose, although not shown, the robot 10 is equipped with an image recognition device.

The robot 10 is fixed to a factory floor 14, and each arm 21, 22, 23 rotates using the parts 15, 16, 17 as fulcrums.
The items 13 on the first pallet 12 are moved to a second pallet (not shown).

Returning to FIG. 1, reference numeral 31 denotes a backup housing which is sandwiched and fixed between the arm 1 and the hand housing 2. A sliding hole 32 opening downward is bored in the backup housing 31.

30 is a main shaft. The main shaft 30 includes an upwardly extending shaft portion 33 and a base portion 34 that is integrally provided with the shaft portion 33.

The shaft portion 33 extends upward through a through hole 35 formed in the hand housing 2, and its tip is slidably inserted into the slide hole 32. The inside of the shaft portion 33 is hollow, and a compression coil spring 36 is disposed between the shaft portion 33 and the backup housing 31. The main shaft 30 is the hand housing 2
It is attached so that it can be displaced relative to the top.

A locking plate 41 is fixed to the shaft portion 33 with a nut 42. The entire main shaft 30 is suspended from the hand housing 2 by a locking plate 41.

An insulating substrate 4 is attached to the base 34 of the main shaft 30.
4 is fixed by a bolt 45. 39 is a knock pin. The insulating substrate 44 is made of aluminum alloy to insulate magnetic lines of force.

A right support 47 and a left support 48 are fixed to both left and right ends of the insulating substrate 44 by bolts 46 with an interval between them. The right support 47 and the left support 48 extend downward in parallel.

A coil support 52 is fixed between the right support 47 and the left support 48 with bolts 51. Coil support 52 is connected to right support 47 and left support 48 .

A bobbin 53 is attached around the coil support 52, and a coil 54 is wound around the bobbin 53. Therefore, when power is supplied to the coil 54, the coil support 52 becomes an electromagnet.

Work pieces 61 and 62 are attached to the tips of the right support 47 and the left support 48.
Rods 68 and 69 protrude outward from the respective workpiece pads 61 and 62, and rods 68 and 69 are attached to the right support 47 and the left support 48, respectively.
Elongated holes 78 and 79 are formed into which the holes 69 are slidably inserted. The long holes 78 and 79 extend in the longitudinal direction.

FIG. 2 is a perspective view of the mounting structure for the workpiece support shown in FIG. 1.

In FIG. 2, 47 is a right support, 48 is a left support, and 61 and 62 are workpiece supports.
Further, 78 and 79 are long holes, and 68 is a rod.

As shown in Fig. 2, rods 68 and 69 protrude outward from the work pieces 61 and 62, and the rods 68 and 69 are slidably inserted into the right support 47 and the left support 48. Long hole 7
It can be seen that numbers 8 and 79 are drilled.

Work piece 61 by rods 68, 69,
62 is suspended from the right support 47 and the left support 48. A sensor mounting member 65 is provided between the workpiece pad 61 and the workpiece pad 62, and the workpiece pad 61 and the workpiece pad 62 are held together by the sensor mounting member 65.

At the tips of the right support 47 and the left support 48, claws 99 facing toward the sensor mounting member 65 are provided, and the workpiece pads 61 and 62 are also provided with stepped portions 98 that align with the claws 99. ing.

The stepped portions 98 of the work pieces 61 and 62 are adapted to be removably engaged with the claws 99 from above. When the right support 47 and the left support 48 are arranged vertically, the stepped portion 98 is aligned with the claw 99, so the work pieces 61 and 62 are integrally attached to the right support 47 and the left support 48. It's summery. However, the workpiece pads 61, 62
When the stepped portion 98 is removed from the pawl 99 by lifting it upward as shown by arrow P, the work pieces 61 and 62 rotate in the front-back direction as shown by arrow M using the rods 68 and 69 as fulcrums. obtain.

Returning to FIG. 1, between the workpiece pad 61 and the workpiece pad 62, there is the sensor mounting member 65, as described above, and the sensor mounting member 65 is attached to the workpiece by the rods 88, 89. It is attached to a pad 61 and a work pad 62. That is, rods 88 and 89 extend from the sensor mounting member 65 to the left and right.
89 is rotatably fitted into sliding holes 91 and 92 formed in the work pieces 61 and 62.
The sensor mounting member 65 is made of aluminum alloy or resin to insulate magnetic lines of force.

A first sensor 66 is attached to the sensor attachment member 65. First sensor 66
A male screw is carved around the sensor mounting member 65, and a female screw is carved in the sensor mounting member 65. The first sensor 66 is attached to the sensor attachment member 65 by screwing the male screw and the female screw together. 67 is a nut for preventing the first sensor 66 from loosening.

3 is a perspective view of the sensor mounting member of FIG. 1; FIG. In FIG. 3, 65 indicates the entire sensor mounting member. 88 and 89 are rods.

Flanges 59 are provided at the front and rear of the sensor mounting member 65, and the work pads (61, 62 in FIG. 1) are sandwiched between the flanges 59.

As can be seen from FIG. 1, the work piece 61 and the work piece 62 are connected to the sensor mounting member 65
Because of this, we are able to become one.

As mentioned earlier, the right support 47 and the left support 48 are provided with claws 99 at their tips facing toward the sensor mounting member 65, and are also aligned with the claws 99 toward the workpiece pads 61 and 62. Stepped part 98
is provided. When the right support 47 and the left support 48 are arranged substantially vertically, the claws 99 are aligned with the stepped portions 98, so the work pieces 61 and 62 are integrated with the right support 47 and the left support 48. It's getting old. However, when the workpiece pads 61, 62 are lifted upward and the claws 99 are removed from the stepped portion 98, the workpiece pads 61, 62 can be rotated in the front-rear direction using the rods 68, 69 as fulcrums.

In FIG. 1, there is a small gap d between the work pieces 61 and 62 and the sensor mounting member 65.
It's open. Because of this gap d, as mentioned above, the work pieces 61 and 62 and the sensor mounting member 65 are separated from each other by the right support 47 and the left support 4.
8, it can smoothly rotate back and forth using the rods 68 and 69 as fulcrums. Moreover, it can be smoothly slid upward.

Further, the centers of gravity of the work pieces 61 and 62 and the sensor attachment member 65 are located below the rods 68 and 69. Therefore, under normal conditions,
The work pieces 61 and 62 and the sensor attachment member 65 are suspended from the right support 47 and the left support 47, and the stepped portions 98 and the claws 99 engage to connect the right support 47 and the left support 47. They are parallel.

Returning to the main shaft 30, a detent pin 71 is fixed to the base 34 of the main shaft 32. The detent pin 71 extends upward,
Through hole 72 bored in hand housing 2
It extends further into the hand housing 2 by penetrating through it. A second sensor 73 is attached to the hand housing 2 above the rotation stopper pin 71. 74 is a nut for preventing the second sensor 73 from loosening.

Returning to the workpiece pads 61 and 62, the workpiece pads 61 and 62 are used to contact the article (workpiece) 13 and attract the article 13 with magnetic force. That is, the right support 47, the left support 48, and the work pieces 61, 62 are made of a magnetic material, for example, soft iron. Therefore, when power is supplied to the coil 54, the coil support 52 becomes an electromagnet, and the right support 47, the left support 48, and the work pieces 61 and 62 are magnetized. Therefore, the item 13 is attracted. In other words, the item 13 is gripped by the hand 5.

In this embodiment, the article 13 has a circular cross-sectional shape, as can be seen from FIG. In addition, the contact portion 8 of the work pieces 61 and 62 with the item 13
5 is shaped to match the shape of the item 13. The work pieces 61 and 62 are aligned with the item 13 and then magnetically attracted to the item 13 to grip the item 13. As mentioned earlier, rather than simply attracting the item 13 with magnetic force, this is done by aligning the shape of the item 13 and increasing the contact area between the item 13 and the workpieces 61 and 62, and then using the magnetic force. This is because the attraction requires less magnetic energy and the entire robot (reference numeral 10 in FIG. 5) can be made smaller.

Coil 54 is not always energized. In FIG. 5, an item 13 aimed into the first pallet 12 by an image recognition device (not shown),
That is, when the item 13 to be gripped by the hand 5 is found, the hand 5 is displaced downward. When the hand 5 approaches the item 13, the first sensor 66 in FIG. 1 senses this and sends a signal to a control device (not shown). Then, the control device controls the coil 54.
to supply power. When power is supplied to the coil 54, the workpiece 61 and the workpiece 62 are magnetized, so the article 13 is attracted to the workpiece 61 and the workpiece 62. At the same time, upon receiving the output signal from the first sensor 66, the control device stops the downward movement of the hand 5. In this way, coil 5
The role of the first sensor 66 is to signal that power is supplied to the hand 4 and to stop the movement of the hand 5.

Since the hand 5 has inertia when moving downward, the workpiece holder 61 and the workpiece holder 62 will move slightly downward even after gripping the item 13. Therefore, the main shaft 30 tends to move slightly upward relative to the hand housing 2. For this purpose, as described above, the main shaft 30 is attached to the hand housing 2 so as to be relatively displaceable in the upward direction.

Bearing metals 81 and 82 are provided between the shaft portion 33 and the through hole 35 of the hand housing 2, and between the detent pin 71 and the through hole 72 of the hand housing 2 to improve sliding. . Both bearing metals 81 and 82 are fixed to the hand housing 2. Also,
A bearing metal 83 is also attached to the backup housing 31 for the same reason.

The second sensor 73 detects the approach of the detent pin 71 when the downward movement of the hand 5 does not stop despite the output signal of the first sensor 66 due to some abnormality. This is to send a signal for an emergency stop of arm 1 to the control device that does not operate. This is the role of the second sensor 73.

FIG. 4 is a perspective view of the robot shown in FIG. 1 with its hand grasping an item.

In FIG. 4, 2 is a hand housing, 30
is the main shaft, 47 and 48 are the right support and left support, and 61 and 62 are the work pads. Further, 65 is a sensor attachment member, 54 is a coil, and 13 is an article.

When gripping the item 13 with the work pieces 61 and 62, an image recognition device (not shown) always controls the axial direction of the item 13 and the position of the hand 5 so that the positional relationship is optimal for gripping the item 13.

The operation of this embodiment will be explained.

In this embodiment, as described above, when the right support 47 and the left support 48 are arranged substantially vertically, the claws 99 are aligned with the stepped portions 98, so the workpiece pads 61, 62 is right support 4
7 and the left support 48. Therefore, in Figure 6 (in Figure 6, 5 is the entire hand,
47 and 48 are the right support and left support, 30 is the main shaft, and 2 is the hand housing), the item 13 is arranged diagonally.
Even when the hand 5 approaches the work piece from diagonally above, the work pieces 61 and 6
2 is parallel to the right support 47 and the left support 48. Therefore, the work pieces 61 and 62 are perpendicular to the item 13 even at the moment of contact with the item 13.

When the work pieces 61 and 62 contact the item 13 at right angles and receive a reaction force from the item 13, the work pieces 61 and 62 are lifted in the direction of arrow P, and the stepped portion (98 in FIG. 2) is lifted. Claw (symbol 9 in Figure 2)
9), the work pieces 61 and 62 rotate in the direction of arrow M using the rods 68 and 69 as fulcrums. Therefore, even if the item 13 is arranged at an angle, the work pieces 61 and 62 completely cover the item 1.
It will be consistent with 3. Therefore, the item 13 can be gripped securely.

Further, according to this embodiment, only the portions necessary for gripping the article 13, that is, the workpiece pads 61 and 62, are movable, so the rotating portions are small. Therefore, the responsiveness when matching the item 13 is good.

Furthermore, when the workpiece pads 61 and 62 align with the item 13, it is inevitable that some impact will be applied to the product 13, but in this embodiment, the only movable part is the workpiece pads 61 and 62, which is small.
The impact is less. Therefore, the item 13 is hardly scratched.

Further, in this embodiment, work pieces 61 and 6 are provided at the ends of the right support 47 and the left support 48.
2 is attached, and the workpiece pads 61, 6
2 is used to grasp an item (work) 13. In other words, right support 47 and left support 4
8 does not grasp the item 13 at the tip. Therefore, when the surface marked 85 in FIG. 1 becomes worn, only the workpiece pads 61 and 62 need to be replaced, and there is no need to replace the entire hand 5. Therefore, according to this embodiment, replacement can be done in a short time and costs can be kept low.

Further, according to this embodiment, even when gripping another type of item 13 with a different diameter, the workpiece support 6
Since only the parts 1 and 62 need to be replaced according to the item 13, there is an advantage that the versatility of the hand 5 is greatly increased.

Although a specific embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and includes various embodiments within the scope of the utility model registration claims.

[Effect of idea]

According to the present invention, when the hand approaches an item placed at an angle from above, the workpiece stopper does not hang down vertically, so even the item placed at an angle can be securely gripped. It has the effect of being able to do it.

Further, according to the present invention, since only the part necessary for gripping the article, that is, the workpiece stopper, is movable, the rotating part is small. Therefore, the responsiveness when matching the item is good.

Furthermore, when the workpiece pad is aligned with the article, it is inevitable that some impact will be applied to the article, but in the present invention, the only movable part is the workpiece pad, which is small, so the impact is small. Therefore, there is almost no chance of scratches on the item.

Furthermore, in the present invention, even if the workpiece pad becomes worn, only the workpiece pad needs to be replaced, and there is no need to replace the entire hand, so replacement can be done in a short time and does not increase costs.

Further, according to the present invention, even when gripping a different type of item, only the workpiece support can be replaced, which greatly increases versatility.

[Brief explanation of the drawing]

1 is a vertical cross-sectional view of a robot hand according to an embodiment of the present invention, FIG. 2 is a perspective view of the mounting structure of the workpiece support shown in FIG. 1, and FIG. 3 is a view of the sensor shown in FIG. 1. FIG. 4 is a perspective view of the attachment member, and FIG. 4 is a perspective view of the robot hand shown in FIG. 1 gripping an item. FIG. 5 is a side view of the robot to which the hand shown in FIG. 6 is an explanatory diagram of the operation of the hand of FIG. 1, FIG. 7 is a perspective view of the conventional robot hand, and FIG. 8 is an explanatory diagram of the operation of the conventional robot hand. 1...Arm, 5...Hand, 10...Robot, 30...Main shaft, 47...Right support, 48...Left support, 54...Coil (driving means), 61, 62...Workpiece support , 85...
A contact surface of the work piece against the item, 98...Stepped portion, 99...Claw.

Claims (1)

[Claims for Utility Model Registration] A robot having a main shaft attached to the tip of an arm of the robot, and a right support and a left support fixed to the main shaft and extending in parallel with a certain distance between them. In the hand, a workpiece for gripping an item is attached to the tips of the right support and the left support, and a surface of the workpiece that comes into contact with the item has a shape that matches the shape of the item. Further, the right support and the left support are provided with claws extending toward the workpiece at the tips thereof, and the workpiece is provided with a stepped portion that engages with the claws. The stepped portion of the workpiece pad is configured to removably engage with the pawl from above, and when the pawl and the stepped portion are engaged, the workpiece pad is removably engaged with the pawl from above. The work piece is made integral with the right support and the left support, and when the pawl and the stepped portion are disengaged, the work piece slides vertically with respect to the right support and the left support. movable and rotatable in the front and rear directions,
The robot hand is further characterized in that the right support and the left support are provided with driving means for gripping the object by applying the workpiece support.