JP6253750B1 - Robot hand - Google Patents

Abstract

The present invention provides a robot hand excellent in work efficiency in which there is no risk of load displacement or dropping even when a robot body is operated at high speed. A robot hand includes a hand main body portion and a load gripping mechanism portion. The gripping mechanism unit 3 includes a first suction pad 4 that is attracted to the upper surface of the load, a second suction pad 40 that is attracted to the side surface of the load, and a fork claw 5 that supports the lower surface of the load. The first suction pad 4 is attached to the hand main body 2. The second suction pad 40 is attached to the movable plate 8 provided on the lower surface of the hand main body 2. The movable plate 8 supports the upper ends of the drive link 61 and the driven link 62 constituting the parallel link mechanism 6 on both sides. The base end portion of the fork claw 5 is attached to the lower ends of the links 61 and 62. A reciprocating mechanism 7 for reciprocating the fork claws 5 with respect to the load is connected to the drive links 61 on both sides. [Selection] Figure 1

Description

  The present invention relates to a robot hand attached to the tip of an arm of a robot body, and more particularly to a robot hand suitable for an operation of unloading a load loaded on a pallet or a carriage.

  Conventionally, as this type of robot hand, it has a fork claw that moves forward and backward by a drive mechanism incorporated in the hand main body, and a work pressing mechanism that is supported by the hand main body so as to be movable up and down and has a suction pad attached to the lower end. There is something. To grab a load with this robot hand, lower the suction pad to attract the upper surface of the load, then raise the suction pad to raise the load slightly, then advance the fork claw to the lower surface of the load. After the insertion, the suction pad is lowered to hold the load between the suction pad and the fork claw. Thereafter, the robot body is turned to move the load to a predetermined position together with the robot hand, and then the fork claws are moved backward to place the load on, for example, a roller conveyor (see, for example, Patent Document 1).

JP-A-6-320464

  However, since the robot hand configured as described above holds the load from above and below, if a large centrifugal force acts on the load when the robot body turns, the load may be displaced or the load may come off and fall off. Therefore, the robot body cannot be operated at a high speed. In order to grip the load, the suction pad is lowered and sucked onto the upper surface of the load, then the suction pad is lifted to lift the load, and then the fork claw is inserted into the lower position of the load and then sucked. It requires a procedure of lowering the pad and lowering the load onto the fork claw.In particular, after inserting the fork claw into the lower position of the load, it is necessary to lower the load onto the fork claw. There is a problem of lowering.

  The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a robot hand having excellent work efficiency in which there is no possibility of load displacement or dropping even when the robot body is operated at high speed. .

  A robot hand according to the present invention includes a hand main body connected to the tip of an arm of a robot main body, and a load gripping mechanism provided in the hand main body. The gripping mechanism section includes a first suction pad that holds the load by sucking the upper surface of the load, a second suction pad that sucks the side surface of the load and holds the load, and a fork claw that supports the lower surface of the load Is included. The first suction pad is attached to the hand main body. The second suction pad is attached to a movable member provided to the hand main body so as to be able to approach and separate from the side with respect to the load. At the position behind the second suction pad of the movable member, upper ends of two parallel links constituting a parallel link mechanism are supported on both sides, respectively, and the fork claws are attached to the lower ends of the links. The end portion is attached so that the tip portion faces the direction of the load. A reciprocating mechanism for reciprocating the fork claw with respect to the load is connected to one of the links on both sides.

In order to unload a load loaded on a cart or a pallet by the robot hand having the above-described configuration, after the robot body is moved by the robot body and the load is positioned in the space for supporting the load, The upper surface of the load is sucked by the suction pad, and then the second suction pad is brought close to the load by the movable member to suck the side surface of the load. Since the load is held by the suction force of each of the first and second suction pads, the robot main body slightly moves the robot hand upward to lift the load and form a space for the fork claws to enter under the load.
Next, when the reciprocating mechanism is operated, the fork pawls move forward toward the load and are guided below the load to support the lower surface of the load. In this case, since the reciprocating mechanism is composed of two parallel links constituting the parallel link mechanism, the fork pawls move upward while drawing an arc and come into contact with the lower surface of the load. As a result, the upper and lower surfaces and side surfaces of the load are gripped by the gripping mechanism portion of the robot hand, and the load is conveyed to a predetermined position together with the robot hand by the turning operation of the robot body.

  Next, on the roller conveyor, for example, the reciprocating mechanism is operated to move the fork claw back in the direction away from the load, and retract from the lower side of the load. In this case, the fork pawls move backward while descending in an arc, and leave the lower surface of the load. The load is held by the first and second suction pads. Next, when the robot body lowers the robot hand and places the load on, for example, a roller conveyor, the movable member is moved backward to move the second suction pad. Retreats away from the side of the load. Thereafter, when the robot body raises the robot hand, the first suction pad is also separated from the upper surface of the load, and the load is released from the robot hand.

  In a preferred embodiment of the present invention, each of the first and second suction pads applies a suction force by a vacuum device to each suction surface.

  According to this embodiment, when the suction force by the vacuum device is applied to the suction surface by placing the first suction pad on the top surface of the load, the pressure inside the suction pad is reduced, and the top surface of the load is placed on the first suction pad. Adsorbed. The same applies to the case where the suction force by the vacuum device is applied to the suction surface by placing the second suction pad on the side surface of the load, and the side surface of the load is sucked to the second suction pad.

  The robot hand according to the present invention is further provided with a stopper that abuts the side surface of the load on the hand main body.

  According to this embodiment, when the robot body moves the robot hand so that the load is located in the space that supports the load of the robot hand, the load is applied to the robot hand by the stopper hitting the side of the load. After positioning, the upper surface of the load is sucked by the first suction pad.

  According to the present invention, when the load is gripped by the gripping mechanism and transported, the upper and lower surfaces of the load are sandwiched and the side surfaces are held by suction, so that the load can be prevented from being displaced or dropped, and the robot body can be moved at high speed. It can be operated. In addition, the fork claws move forward and come into contact with the lower surface of the load, and the fork claws move downward and move backward to move away from the lower surface of the load, so it takes time to hold the load and release the load. In addition, work efficiency can be improved.

It is a side view of the robot hand which is one Example of this invention. It is a rear view of a robot hand. It is a top view of a robot hand. It is a top view of a fork nail. It is a side view which shows operation | movement (1) (2) which unloads a load from a pallet. It is a side view which shows operation | movement (3) and (4) which unloads from a pallet. It is a side view which shows operation | movement (1) (2) which loads a load on a roller conveyor. It is a side view which shows the operation | movement (3) which loads a load on a roller conveyor.

  1 to 3 show a configuration of a robot hand 1 according to an embodiment of the present invention. In the illustrated robot hand 1, a load gripping mechanism 3 is provided below the hand main body 2. The gripping mechanism section 3 is for gripping the load 10 stacked in an aligned state on the pallet 11, and the load 10 is transported to a predetermined position by the operation of a robot body (not shown), on a roller conveyor, etc. Placed in. The hand main body 2 is constituted by a metal plate 20 having a rectangular shape in plan view, and rising walls 21 and 21 are formed on both side edges of the plate 20. A central portion of the upper surface of the plate member 20 has a connection portion 22 to which the tip of the arm 12 of the robot body is connected by a bolt or the like. Although not shown, the robot body is installed on the floor so as to be able to turn, and includes an arm 12 having a plurality of joints. The robot hand 1 is moved up and down and left and right by the turning motion of the robot body and the expansion and contraction motion of the arm 12, and can approach the position of the load 10 and grasp the load 10.

Below the hand main body 2 is a space (hereinafter referred to as “load support space P”) that supports the load 10 on the front side, and a gripping mechanism portion 3 is provided corresponding to the load support space P. ing. In the figure, (F) is the front side of the robot hand 1, and (B) is the rear side of the robot hand 1.
The gripping mechanism section 3 includes a plurality of (four in this embodiment) first suction pads 4 that hold the load 10 by sucking the upper surface a of the load 10 located in the load support space P, and the load 10 A plurality of (two in this embodiment) second suction pads 40 for sucking the rear side surface c and holding the load, a stopper 30 with which the rear side surface c of the load 10 abuts, It includes a plate-like metal fork claw 5 that supports the lower surface b.

  The four first suction pads 4 are arranged in two rows and two columns, and are arranged on the lower surface of the hand main body 2 with the suction surface facing downward toward the load support space P. The two second suction pads 40 are arranged side by side, and are arranged sideways with the suction surface facing the load support space P. The first suction pad 4 is fixedly attached to the lower surface of the hand main body 2. The second suction pad 40 is attached to a horizontal movable plate 8 as a movable member provided on the lower surface of the hand main body 2 so as to be close to and away from the load support space P. The first and second suction pads 4 and 40 are connected to a vacuum device (not shown) via hoses 41 and 42, and the suction pads 4 and 40 are negatively pressured by the vacuum device, and the respective suction pads 4 and 40 are sucked. Apply a suction force to the surface.

  In this embodiment, the stopper 30 is configured with a detection rod of an object detection sensor that detects that the load 10 has come into contact, and the stopper 30 is located near the first suction pad 4 on the lower surface of the hand main body 2. It is attached so as to face the support space P. When the object detection sensor detects the contact of the load 10, the first suction pad 4 starts the suction operation. The stopper 30 is not limited to a rod-like one, and may be a plate-like one.

  A support frame portion 82 that supports the two second suction pads 40 is integrally provided on the lower surface of the movable plate 8. The movable plate 8 is supported by the lower surface of the hand main body 2 through the guide mechanism 83 so as to move freely, and is reciprocated by the drive mechanism 9. In this embodiment, a “linear way” (registered trademark: manufactured by Nippon Thomson Co., Ltd.) is used as the guide mechanism 83, and a pair of track rails 84, 84 attached to both sides of the lower surface of the hand body 2. , And two sliders 85, 85 that are slidable with respect to each track rail 84. The movable plate 8 is fixed to the sliders 85 and 85.

  The drive mechanism 9 is composed of an air cylinder 90. The air cylinder 90 is fixed to the center of the lower surface of the hand body 2, and the tip of the rod 91 is connected to an end plate 92 attached to the upper surface of the movable plate 8.

  The fork claw 5 has a thickness that decreases toward the tip, and is integrally provided with a rectangular attachment plate portion 51 and a bifurcated support plate portion 52, as shown in FIG. Shaft support plates 53 and 53 are respectively attached to both side ends of the upper surface of the mounting plate portion 51. At the front and rear positions of each shaft support plate 53, lower ends of parallel links 61 and 62, which will be described later, are pivotally supported by a pivot 63 so that the tip of the fork claw 5 faces the load support space P. The support plate portion 52 of the fork claw 5 has a length and a width capable of supporting the lower surface of the load 10, and the rollers of the roller conveyor 101 for placing the load 10 between the left and right support plate portions 52, 52. A groove 54 having a groove width larger than 100 is interposed.

  On both side edges of the lower surface of the movable plate 8, shaft support plates 86, 86 are attached at positions behind the second suction pad 40. Two pivot shafts 64 are pivotally supported between the pivot plates 86 and 86, and upper ends of the drive link 61 and the driven link 62 constituting the parallel link mechanism 6 are pivotally supported at both ends of each pivot shaft 64, respectively. . The drive link 61 and the driven link 62 have the same length and are parallel to each other, and the driven link 62 follows the drive link 61 to perform the same operation, so that the link between the two links 61 and 62 is performed. Parallelism is maintained. An air cylinder 70 constituting the reciprocating mechanism 7 is supported between the shaft support plates 86 and 86 via an attachment plate 87. The reciprocating mechanism 7 reciprocates the fork pawl 5 with respect to the load support space P via the parallel link mechanism 6, and the tip of the rod 71 of the air cylinder 70 is connected to the drive link 61 of the parallel link mechanism 6 on both sides. It is connected to the center of the length.

  In order to unload the load 10 loaded on, for example, the pallet 11 by the robot hand 1 having the above-described configuration, the robot body moves the robot hand 1 as shown in FIG. Place load 10 on P. When the rear side surface c of the load 10 hits the stopper 30, first, a suction force acts on the suction surface of the first suction pad 4, and the first suction pad 4 sucks the upper surface of the load 10. Next, as shown in FIG. 5A (2), when the drive mechanism 9 is driven to extend the rod 91 of the air cylinder 90, the slider 85 of the guide mechanism 83 slides along the track rail 84, The movable plate 8 moves integrally toward the load 10, and the second suction pad 40 approaches the load 10. When a suction force is applied to the suction surface of the second suction pad 40, the second suction pad 40 sucks the side surface c of the load 10.

  Since the upper surface a and the side surface c of the load 10 are held by the suction force of the first and second suction pads 4 and 40, the robot body moves the robot hand 1 upward as shown in FIG. When the load 10 is lifted slightly, the space S into which the fork claws 5 enter is formed below the load 10.

  Next, as shown in FIG. 5B (4), when the air cylinder 70 of the reciprocating mechanism 7 is operated to extend the rod 71, the drive link 61 constituting the parallel link mechanism 6 on both sides of the hand body 2. Travels toward the load 10 with the upper end as a fulcrum, and the driven link 62 follows the drive link 61 while keeping parallel to it. At this time, as indicated by a one-dot chain line in the figure, the fork claw 5 at the lower end moves upward while drawing an arc, and comes into contact with the lower surface b of the load 10 and stops. As a result, the upper surface a, the lower surface b, and the rear side surface c of the load 10 are gripped by the gripping mechanism portion 3 of the robot hand 1, and the load 10 is integrated with the robot hand 1 by the turning motion of the robot body and the expansion and contraction motion of the arm 12. As shown in FIG. 6A (1), for example, it is conveyed to a position above the roller conveyor 101.

  When the rod 71 is contracted by operating the air cylinder 70 of the reciprocating mechanism 7 on the roller conveyor 101, the drive links 61 constituting the parallel link mechanism 6 are separated from the load 10 with the upper ends as fulcrums on both sides of the hand body 2. It moves back in the direction, and the driven link 62 follows the drive link 61 while keeping it parallel. At this time, as indicated by the alternate long and short dash line in the figure, the fork pawl 5 at the lower end moves downward while moving downward and draws away from the lower surface b of the load 10.

  The load 10 is held by the suction force by the first and second suction pads 4 and 40 as shown in FIG. 6-1 (2), and then as shown in FIG. 6-2 (3). The robot body lowers the robot hand 1 and places the load 10 on the roller conveyor 101. Thereafter, when the drive mechanism 9 is driven to contract the rod 91 of the air cylinder 90, the slider 85 of the guide mechanism 83 slides along the track rail 84, and the movable plate 8 moves away from the load 10, The second suction pad 40 is separated from the side surface c of the load 10. Thereafter, when the robot body raises the robot hand 1, the first suction pad 4 is separated from the upper surface a of the load 10, and the load 10 is released from the robot hand 1.

DESCRIPTION OF SYMBOLS 1 Robot hand 2 Hand main body 3 Gripping mechanism part 4 1st adsorption pad 5 Fork nail 6 Parallel link mechanism 7 Reciprocating mechanism 8 Movable plate 10 Load 12 Robot arm 30 Stopper 40 2nd adsorption pad 61 Drive link 62 Follow link P Load support space

Claims (3)

A hand main body connected to a tip of an arm of the robot main body, and a load gripping mechanism provided in the hand main body, the gripping mechanism holding the load by adsorbing an upper surface of the load. A suction pad, a second suction pad that holds the load by sucking a side surface of the load, and a fork claw that supports a lower surface of the load, wherein the first suction pad is attached to the hand main body, The second suction pad is attached to a movable member provided so as to be able to approach and separate from the side of the hand main body with respect to the load,
At the position behind the second suction pad of the movable member, upper ends of two parallel links constituting a parallel link mechanism are supported on both sides, respectively, and the fork claws are attached to the lower ends of the links. A robot hand in which an end portion is attached so that a tip portion faces a load direction, and a reciprocating mechanism for reciprocating the fork claw with respect to the load is connected to one link on both sides.   The robot hand according to claim 1, wherein each of the first and second suction pads applies a suction force by a vacuum device to each suction surface.   3. The robot hand according to claim 1, further comprising a stopper that abuts a side surface of a load on the hand main body. 4.

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