JP2022110868A - Article accumulation device - Google Patents

Abstract

To provide an article accumulation device which achieves efficiency improvement of article accumulation.SOLUTION: An article accumulation device 10 includes a first conveyor 91, a parallel link robot 82, and a control part 50. The parallel link robot 82 grips an article P on a conveyance surface of the first conveyor 91 and accumulates the article P at an accumulation position. The control part 50 controls operation of the parallel link robot 82 on the basis of a position and a posture of the article P on the conveyance surface. The parallel link robot 82 has a plurality of gripping parts. When the plurality of gripping parts sequentially grip the article P, the control part 50 calculates whether or not a contour in plan view of the gripping parts or a contour in plan view of the gripping parts including the article P gripped by the gripping parts become within an interference avoidance range AR to prevent interference with a safety frame SF, and determines whether or not the article P can be gripped by the parallel link robot 82.SELECTED DRAWING: Figure 4

Description

The present invention relates to an article stacking device.

Conventionally, as disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 2018-104179), it has a function of picking up an article being conveyed on one conveyor and moving the article to the other conveyor. An article stacking device having a gripper is known.

In the article stacking apparatus disclosed in Patent Document 1, depending on the position of the gripping section, the position of the article, and the attitude of the article, the gripping section may interfere with objects present around the gripping section. In order to avoid such a situation, the movable range of the gripping section should be adjusted so that the gripping section does not interfere with the object regardless of the position or posture of the gripping section. can be set.

However, when the movable range of the grip portion is set in the manner described above, the movable range of the grip portion may be excessively restricted. As a result, it is conceivable that some articles pass through the conveyor without being picked up by the gripper. In other words, the article stacking device according to the prior art is inefficient in stacking items.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an article stacking apparatus that suppresses the occurrence of a situation in which a gripping section interferes with an object existing around the gripping section and improves the efficiency of stacking articles.

An article stacking apparatus according to a first aspect of the present invention is an article stacking apparatus in which conveyed articles are moved to a stacking position by a robot and stacked. An article stacking apparatus includes a transport section, a robot, and a control section. The transport unit transports the article. The robot grips the articles on the conveying surface of the conveying section and stacks them at the stacking position. The controller controls the motion of the robot based on the position and orientation of the article on the conveying surface. The robot has a plurality of grippers. The plurality of grippers includes a first gripper and a second gripper that grip an article. When a plurality of gripping portions sequentially grip an article, the control portion determines whether the outer shape of the gripping portions in plan view or the outer shape of the gripping portions including the article gripped by the gripping portions in plan view is the circumference of the plurality of gripping portions. It calculates whether or not the object is within the interference avoidance range where interference with the object does not occur, and determines whether or not the robot can grip the object.

In the article stacking apparatus according to the first aspect, the outer shape of the gripping portion in plan view or the outer shape of the gripping portion including the article gripped by the gripping portion in plan view does not interfere with objects around the plurality of gripping portions. The control unit determines whether or not it is within the interference avoidance range. According to this configuration, there is no risk that the gripping portion or the article gripped by the gripping portion will interfere with surrounding objects. Further, when the control unit determines that the outer shape of the gripping unit in plan view or the outer shape of the gripping unit including the article gripped by the gripping unit in plan view is within the interference avoidance range, the robot does not hold the article. Grasp. Therefore, the efficiency of accumulating articles is improved.

An article stacking apparatus according to a second aspect of the present invention is the article stacking apparatus according to the first aspect. Assuming that the first article is the first article to be gripped by a robot that is not gripping an article, the control unit determines whether or not the robot can grip the first article.

According to this configuration, there is no risk that the gripping portion or the first article gripped by the gripping portion will interfere with surrounding objects. Further, when the control unit determines that the outer shape of the gripping unit including the first article gripped by the gripping unit in a plan view is within the interference avoidance range, the parallel link robot moves to the first object. Grasp an item. Therefore, the efficiency of accumulating articles is improved.

An article stacking device according to a third aspect of the present invention is the article stacking device according to the second aspect. When the next item to be gripped by the robot that has gripped the first item is the second item, the control unit further determines whether or not the robot can grip the second item.

According to this configuration, there is no fear that the gripping section, the first article gripped by the gripping section, or the second article gripped by the gripping section will interfere with surrounding objects. Further, the outer shape of the gripping portion including the first item gripped by the gripping portion and the outer shape of the gripping portion including the second item gripped by the gripping portion fall within the interference avoidance range. When the control unit determines that the parallel link robot grips the second article. Therefore, the efficiency of accumulating articles is improved.

An article stacking device according to a fourth aspect of the present invention is the article stacking device according to the third aspect. The conveying unit is provided over the first range and the second range. The second range is located downstream of the first range in the transport direction of the transport unit. The robot grips the first article with the first gripping part in the first range. The robot grips the second article with the second gripping part in the second range.

An article stacking device according to a fifth aspect of the present invention is the article stacking device according to the fourth aspect. The control unit determines whether or not the first item can be gripped by the second gripping unit when the first gripping unit cannot grip the first item.

An article stacking device according to a sixth aspect of the present invention is the article stacking device according to the first aspect. The control unit determines whether or not the article can be gripped according to the angle with respect to the conveying direction in which the article is conveyed.

In the article stacking apparatus according to the present invention, there is no possibility that the gripping section or the articles gripped by the gripping section will interfere with surrounding objects. Also, in the article stacking apparatus according to the present invention, the efficiency of stacking articles is improved.

1 is a schematic side view of a cartoning machine; FIG. 1 is a schematic diagram of a parallel link robot; FIG. 1 is a schematic diagram of a cartoning robot; FIG. 1 is a schematic diagram of a first conveyor and a second conveyor; FIG. It is a schematic diagram of a box transport conveyor. 3 is a block diagram showing the configuration of a control unit; FIG. FIG. 4 is a plan view showing a first conveyor and articles to be conveyed on the first conveyor; FIG. 4 is a plan view showing a first conveyor and articles to be conveyed on the first conveyor; FIG. 4 is a plan view showing the position of an article predicted by a prediction unit and the posture of a gripper predicted by the prediction unit; FIG. 10 is a plan view showing a first gripping part that grips a first article, a first conveyor, and articles conveyed to the first conveyor; FIG. 4 is a plan view showing the position of an article predicted by a prediction unit and the posture of a gripper predicted by the prediction unit; FIG. 11 is a plan view showing the second gripper gripping a second article after rotating the header by 180°; FIG. 10 is a plan view showing a first gripping part that grips a first article, a first conveyor, and articles conveyed to the first conveyor; FIG. 4 is a plan view showing the position of an article predicted by a prediction unit and the posture of a gripper predicted by the prediction unit; It is a flow chart showing the flow of the operation of the article stacking device. 1 is a diagram showing an article stacking device according to the prior art; FIG. 1 is a diagram showing an article stacking device according to the prior art; FIG. 1 is a diagram showing an article stacking device according to the prior art; FIG.

An article stacking device according to an embodiment of the present disclosure will be described below with reference to the drawings. It should be noted that the following embodiments are specific examples, and do not limit the technical scope, and can be modified as appropriate without departing from the scope of the invention. In addition, in the following explanation, expressions such as vertical, orthogonal, horizontal, parallel, etc. may be used in order to explain directions, positional relationships, etc., but these are strictly vertical, orthogonal, horizontal, parallel, etc. Not only, but also substantially vertical, orthogonal, horizontal, parallel, etc. are included.

(1) Overall Configuration FIG. 1 is a schematic side view showing a boxing device 100 equipped with an article stacking device 10 according to one embodiment of the present invention. 2A to 2D are schematic diagrams showing the configuration of each part of the cartoning apparatus 100. FIG. FIG. 3 is a block diagram of the cartoning device 100. As shown in FIG. FIG. 4 is a plan view schematically showing the first conveyor 91 and the articles P conveyed by the first conveyor 91. As shown in FIG.

The boxing device 100 is a device for putting a plurality of articles P into one box B. As shown in FIG. As shown in FIGS. 1 to 3, the boxing device 100 includes an article stacking device 10, a boxing robot 83, a second conveyor 92, and a box transport conveyor 300. As shown in FIG. The article stacking apparatus 10 mainly includes a first conveyor 91 (corresponding to the "conveyor" in the claims), a parallel link robot 82 (corresponding to the "robot" in the claims), A control unit 50 is provided. Furthermore, here, as an additional configuration, the article stacking device 10 is provided with a camera 21 .

The first conveyor 91 of the article stacking device 10 conveys the articles P put into the boxing device 100 from the article entrance PI one by one. The camera 21 of the article stacking device 10 detects the position and orientation of the articles P flowing on the first conveyor 91 . The parallel link robot 82 of the article stacking device 10 lifts the two articles P on the first conveyor 91 and places the article row R consisting of the two articles P on the second conveyor 92 (see FIG. 2C). The second conveyor 92 makes an article group G consisting of four articles P by adjusting the conveying speed. The boxing robot 83 simultaneously grips the four articles P constituting the article group G and puts the four articles P into the box B waiting in the box waiting section 84 . After the packing robot 83 completes the packing of the article group G, the box B is carried to the next step (for example, the step of closing the top lid of the box B) by the box transfer conveyor 300 .

The cartoning apparatus 100 according to this embodiment also has a safety frame SF for protecting the operator of the cartoning apparatus 100 and the devices around the cartoning apparatus 100 (see FIG. 4). For this reason, each part constituting the cartoning apparatus 100 including the parallel link robot 82 must operate so as not to interfere with the safety frame SF. In this embodiment, the control unit 50 controls the operation of the parallel link robot 82 so that the grip portion of the parallel link robot 82 does not interfere with the safety frame SF. A detailed description will be given below.

(2) Detailed Configuration A detailed configuration of the article stacking device 10 will be described. The article stacking device 10 mainly includes a first conveyor 91 , a parallel link robot 82 and a control section 50 .

(2-1) First conveyor 91
The first conveyor 91 will be described with reference to FIGS. 2C and 4. FIG.

The first conveyor 91 is a belt conveyor having conveyor rollers 91a and endless belts 91b (see FIG. 2C). The conveyor roller 91a is driven by a conveyor motor (not shown). By driving the conveyor roller 91a, the belt 91b rotates, and the article P on the belt 91b is conveyed in the conveying direction D1 (see FIG. 4).

As shown in FIG. 4, the first conveyor 91 is provided over a first range R1 and a second range R2. The first range R1 is a range located on the upstream side of the second range R2 in the article P transport direction D1. The second range R2 is a range located downstream of the first range R1 in the article P transport direction D1.

As shown in FIG. 4, the positions and postures of the articles P conveyed by the first conveyor 91 are various. For example, FIG. 4 shows an article P that is conveyed near the right end of the first conveyor 91 in plan view, and an article P that is conveyed in an oblique posture in plan view (a posture inclined with respect to a direction parallel to the conveying direction D1). An article P is shown. These articles P are gripped by the gripper of the parallel link robot 82 .

(2-2) Parallel link robot 82
Parallel link robot 82 is described with reference to FIGS. 1 and 2A. The parallel link robot 82 is a robot that grips the articles P on the conveying surface of the first conveyor 91 and stacks the gripped articles P at the stacking position. The stacking position is, for example, the transport surface of the second conveyor 92 .

As shown in FIG. 1, the parallel link robot 82 is arranged above the first conveyor 91 . As shown in FIG. 2A , the parallel link robot 82 has a base 821 , an arm 822 , a first suction member 61 , a second suction member 62 and a header 70 . An arm 822 is attached to the base 821 . The lower end of arm 822 is connected to header 70 . The header 70 has a first gripping portion 71 and a second gripping portion 72 . The first suction member 61 has one end connected to the first grip portion 71 and the other end connected to a vacuum pump or a vacuum blower (not shown). The second suction member 62 has one end connected to the second grip portion 72 and the other end connected to a vacuum pump or a vacuum blower (not shown).

The first gripping portion 71 is a gripping portion that grips the first article P1 by air suction. The “first article P1” refers to the article P that is first gripped by the parallel link robot 82 when no article P is gripped. The first gripping part 71 grips the first article P1 in the first range R1 of the first conveyor 91 .

The second gripping portion 72 is a gripping portion that grips the second article P2 by air suction. "Second article P2" refers to an article P to be gripped next by the parallel link robot 82 gripping the first article P1. The second gripping part 72 grips the second article P2 in the second range R2 of the first conveyor 91 .

The parallel link robot 82 according to this embodiment moves the article P from the first conveyor 91 to the second conveyor 92 by performing double picking. Double picking is performed by the header 70 having the first gripping portion 71 connected to the first suction member 61 and the second gripping portion 72 connected to the second suction member 62 in the following manner. First, the parallel link robot 82 brings the first gripper 71 into contact with the first article P1 on the first conveyor 91 to grip the first article P1. Next, the parallel link robot 82 moves the header 70, brings the second gripping part 72 into contact with the second article P2 on the first conveyor 91, and grips the second article P2. Finally, the parallel link robot 82 picks up the two gripped items P1, P2 and places them on the second conveyor 92. In this manner, an article row R is formed on the second conveyor 92 .

(2-3) Control unit 50
The configuration of the control unit 50 according to this embodiment will be described with reference to FIG.

The control unit 50 is implemented by a computer. The control unit 50 is electrically connected to each unit constituting the packing apparatus 100 including the article stacking apparatus 10 by wire or wirelessly so as to be able to transmit and receive control signals, information, and the like. The control unit 50 controls the operation of each unit forming the boxing device 100 including the article stacking device 10 . The control unit 50 includes a control arithmetic device and a storage device. A processor, such as a CPU or a GPU, can be used for the control computing unit. The control arithmetic unit reads a program stored in the storage device and performs predetermined arithmetic processing according to the program. Furthermore, the control arithmetic unit can write the arithmetic result to the storage device and read the information stored in the storage device according to the program. A memory such as a ROM or a RAM can be used as the storage device. The storage device stores a program for controlling the operation of each part of the packaging device 100, a communication protocol used when the packaging device 100 communicates with other devices, and the like. In addition, the storage device stores various kinds of information including the transport speed of the article P by the first conveyor 91 and the moving speed of the header 70 .

FIG. 3 shows various functional blocks implemented by the control arithmetic device. As shown in FIG. 3 , the control unit 50 has functions as an interference avoidance range setting unit 51 , a prediction unit 52 and a determination unit 53 . The interference avoidance range setting unit 51, the prediction unit 52, and the determination unit 53 will be described later.

(2-3-1) Control by Control Unit 50 Control of the parallel link robot 82 performed by the control unit 50 will be described below. As shown in FIGS. 4 and 5, a safety frame SF is provided around the boxing device 100. As shown in FIG. In order to ensure the safety of the boxing device 100, the parallel link robot 82 must operate without interfering with the safety frame SF. Specifically, the parallel link robot 82 must perform double picking while avoiding contact with the safety frame SF. Among the parts constituting the parallel link robot 82, the first gripping part 71 and the second gripping part 72 are particularly likely to interfere with the safety frame SF. As described above, the position and orientation (inclination) of the articles P conveyed to the first conveyor 91 vary. This is because it is necessary to frequently repeat the movement in the direction.

Also, if the outer shape of the article P is larger than the outer shape of the first gripping portion 71 or the second gripping portion 72, the article P may interfere with the safety frame SF. For example, when the outer shape of the article P is larger than the outer shape of the first gripping portion 71, depending on the position and orientation of the first gripping portion 71, even if the first gripping portion 71 does not interfere with the safety frame SF, the first gripping portion A situation may occur in which the article P gripped by 71 interferes with the safety frame SF. Taking these points into consideration, the control section 50 must control the operation of the parallel link robot 82 . The control unit 50 performs calculations by the interference avoidance range setting unit 51 , the prediction unit 52 , and the determination unit 53 in order to control the operation of the parallel link robot 82 .

(2-3-1-1) Interference avoidance range setting unit 51
The interference avoidance range setting unit 51 is a functional unit that sets the interference avoidance range AR. The interference avoidance range AR is defined by the outer shape of the gripping portion (here, the first gripping portion 71 or the second gripping portion 72) in plan view, or the outer shape of the gripping portion including the article P gripped by the gripping portion in plan view. , is a range that does not cause interference with surrounding objects (here, the safety frame SF). The interference avoidance range setting unit 51 is set based on, for example, the position of the safety frame SF confirmed through the camera 21 and the position of the first conveyor 91 . As long as the outer shape of the gripping portion in plan view or the outer shape of the gripping portion including the article P gripped by the gripping portion in plan view is within the interference avoidance range AR, the gripping portion or the gripping portion is gripped. The article P does not interfere with surrounding objects. The interference avoidance range AR is, for example, the range indicated by the dashed line in FIG. 5A.

(2-3-1-2) Predictor 52
The prediction unit 52 is a functional unit that predicts the position at which the article P is gripped and the posture of the gripping section that grips the article P. FIG. Below, the position of the article P predicted by the prediction unit 52 may be referred to as "predicted position". Also, hereinafter, the posture of the grip predicted by the prediction unit 52 may be referred to as a “predicted posture”. The prediction unit 52 is based on the current position of the article P photographed by the camera 21, the current position of the header 70 photographed by the camera 21, the conveying speed of the article P by the first conveyor 91, the moving speed of the header 70, and the like. , to calculate the predicted position and predicted attitude.

(2-3-1-3) Determination unit 53
When the article P is at the predicted position and the gripping section assumes the predicted posture, the determination section 53 determines the outer shape of the gripping section in plan view, or the outline of the gripping section including the article P gripped by the gripping section in plan view. is within the interference avoidance range AR. The control unit 50 determines whether or not the parallel link robot 82 can grip the article P based on the determination by the determination unit 53 . Specifically, when the article P is at the predicted position and the gripping section assumes the predicted posture, the outer shape of the gripping section in plan view, or the gripping section including the article P gripped by the gripping section in plan view When the determination unit 53 determines that the outer shape is within the interference avoidance range AR, the control unit 50 causes the parallel link robot 82 to grip the article P. On the other hand, when the article P is at the predicted position and the gripping section assumes the predicted posture, the outline of the gripping section in plan view or the outline of the gripping section including the article P gripped by the gripping section in plan view is , the control unit 50 cancels the gripping of the article P by the parallel link robot 82 when the judgment unit 53 judges that the object P is not within the interference avoidance range AR.

(3) Operation of Parallel Link Robot 82 Operation of the parallel link robot 82 controlled by the control section 50 will be described with reference to FIGS. 5 to 7A. FIG. 5 shows a first conveyor 91 that conveys a plurality of articles PA, PB, and PC, a first gripping section 71 that does not grip an article P, and a second gripping section 72 that does not grip an article P. It is shown. As shown in FIG. 5, among the plurality of articles PA, PB, and PC, the article PA is positioned furthest downstream in the conveying direction D1, and the article PC is positioned furthest upstream in the conveying direction D1. Here, the article PA, the article PB, and the article PC all have the same external shape, and the article PA, the article PB, and the article PC all have external shapes larger than the external shapes of the first gripping portion 71 and the second gripping portion 72. Assuming a situation such as

In the situation shown in FIG. 5, when the camera 21 detects that the article PA is within the first range R1, the control unit 50 starts calculation related to gripping the article PA. The parallel link robot 82 does not grip the article P as described above. Further, as described above, the first gripping portion 71 is a gripping portion that grips the first article P1 in the first range R1 of the first conveyor 91 . Therefore, in the situation shown in FIG. 5, the control unit 50 determines whether or not the article PA can be gripped by the first gripping unit 71 in the first range R1.

In order to determine whether or not the article PA can be gripped by the first gripping section 71, the prediction section 52 predicts the position at which the article PA is gripped, the posture of the first gripping section 71 that grips the article PA, The posture of the second gripping part 72 that does not grip the article PA is predicted. FIG. 5A shows an example of a specific predicted position of the article PA, a specific predicted attitude of the first gripping part 71, and a specific predicted attitude of the second gripping part 72. FIG. As shown in FIG. 5A , here, the prediction unit 52 predicts that the article PA will be gripped by the first gripping unit 71 at a position near the center of the first conveyor 91 . Further, as shown in FIG. 5A, the prediction unit 52 predicts that the first gripping unit 71 that grips the article PA takes a posture whose longitudinal direction is parallel to the conveying direction D1. Further, as shown in FIG. 5A, the prediction unit 52 predicts that when the first gripping unit 71 grips the article PA, the second gripping unit 72 takes a posture whose longitudinal direction is parallel to the conveying direction D1. is doing.

Judgment unit 53 that refers to the predicted position and predicted orientation as shown in FIG. 5A determines that article PA is at the predicted position and first gripping unit 71 and second gripping unit 72 assume the predicted orientation. It is determined that both the outer shape of the first grip portion 71 in plan view and the outer shape of the second grip portion 72 in plan view are within the interference avoidance range AR. According to the determination made by the determination unit 53, the control unit 50 causes the first gripping unit 71 to grip the article PA.

The control unit 50 that has caused the first gripping part 71 to grip the article PA next determines whether or not the second gripping part 72 can grip the article PB. FIG. 6 shows a first conveyor 91 that conveys a plurality of items PB and PC, and a parallel link robot 82 that grips the item PA with the first gripping section 71 . As described above, the article PB is gripped by the second gripping portion 72 in the second range R2.

In order to determine whether or not the article PB can be gripped by the second gripping part 72 in the second range R2, the prediction part 52 predicts the position where the article PB is gripped, Prediction of the posture and prediction of the posture of the first gripping part 71 that has already gripped the article PA are performed. FIG. 6A shows an example of a specific predicted position of the article PB, a specific predicted posture of the second gripping portion 72, and a specific predicted posture of the first gripping portion 71. FIG. The judgment unit 53 refers to the predicted position and the predicted posture as shown in FIG. 6A, and when the article PB is at the predicted position and the second gripping unit 72 takes the predicted posture, the second gripping unit 72 including the article PB It is determined that the outline in plan view is within the interference avoidance range AR. However, when the first gripping portion 71 assumes the predicted posture, the determining portion 53 determines that the planar view of the first gripping portion 71 including the article PA does not fall within the interference avoidance range AR (specifically, , the article PA gripped by the first gripping portion 71 is not within the interference avoidance range AR). According to the determination made by the determination unit 53, the control unit 50 cancels gripping of the article PB.

Regarding the gripping of the article PB by the second gripping part 72 in the situation shown in FIG. It is also conceivable to allow the second gripping part 72 to grip the article PB (see FIG. 6B). In gripping in the mode shown in FIG. 6B, the outer shape of the first gripping portion 71 gripping the item PA in plan view and the outer shape of the second gripping portion 72 gripping the item PB in plan view are different. Both are within the interference avoidance range AR. However, gripping in such a manner is not preferable. This is because rotating the header 70 by 180° may lead to a loss of time and a decrease in the efficiency of stacking articles. Also, when the header 70 is rotated by 180°, the article PA may be shaken off from the first gripping portion 71 . Furthermore, when the article PB is gripped by the second gripping portion 72 after the header 70 is rotated by 180°, the orientation of the item PA gripped by the first gripping portion 71 and the gripped portion of the second gripping portion 72 are different. It is also conceivable that the orientation of the article PB being held may be different. For this reason, the control unit 50 according to the present embodiment ensures that the outer shape of the gripping portion in plan view or the outer shape of the gripping portion including the article P gripped by the gripping portion in plan view falls within the interference avoidance range AR. If not, immediately cancel the grasp.

After canceling the gripping of the article PB by the second gripping section 72, the control section 50 next determines whether or not the article PC can be gripped by the second gripping section 72. FIG. FIG. 7 shows a first conveyor 91 that conveys a plurality of items PB and PC, and a parallel link robot 82 that grips the item PA with the first gripping portion 71 .

In order to determine whether or not the article PC can be gripped by the second gripping section 72, the prediction section 52 predicts the position at which the article PC is gripped, the posture of the second gripping section 72 that grips the article PC, The posture of the first gripper 71 that has already gripped the article PA is predicted. FIG. 7A shows an example of a specific predicted position of the article PC, a specific predicted attitude of the second gripping part 72, and a specific predicted attitude of the first gripping part 71. FIG. Judgment unit 53 that refers to the predicted position and the predicted orientation as shown in FIG. 7A determines that article PC is at the predicted position and first gripping unit 71 and second gripping unit 72 assume the predicted orientation, and that article PA is included. It is determined that both the outer shape of the first gripping portion 71 in plan view and the outer shape of the second gripping portion 72 including the article PC in plan view are within the interference avoidance range AR. According to the determination made by the determination unit 53, the control unit 50 causes the second gripping unit 72 to grip the article PC.

Finally, the parallel link robot 82 lifts the two gripped articles PA, PC and places them on the second conveyor 92 . In this manner, an article row R is formed on the second conveyor 92 .

(4) Overall Operation The operation of the article stacking apparatus 10 already described will be briefly described using the flowchart shown in FIG. When receiving the operation start command, the article stacking apparatus 10 operates according to the flow shown in steps S1 to S11 in FIG. Note that the operation flow shown in FIG. 8 is an example, and can be changed as appropriate. For example, the order of the steps may be changed within a consistent range, some steps may be executed in parallel with other steps, and other steps may be newly added.

In step S1, the interference avoidance range setting unit 51 sets the interference avoidance range AR.

In step S<b>2 , the camera 21 detects the article P (the first article P<b>1 ) flowing on the first conveyor 91 .

In step S3, the prediction unit 52 makes a prediction.

In step S<b>4 , based on the prediction of the prediction section 52 , the determination section 53 determines whether or not the article P can be gripped by the first gripping section 71 . When the determining unit 53 determines that the first gripping unit 71 can grip the article P (Yes in step S4), the operation of the article stacking device 10 proceeds to step S5. When the determination unit 53 determines that the article P cannot be gripped by the first gripping unit 71 (No in step S4), the operation of the article stacking device 10 returns to step S2.

In step S5, the first gripping part 71 grips the first article P1.

In step S<b>6 , the camera 21 detects the article P (the second article P<b>2 ) flowing on the first conveyor 91 .

In step S7, the prediction unit 52 makes a prediction.

In step S<b>8 , based on the prediction of the prediction section 52 , the determination section 53 determines whether or not the article P can be gripped by the second gripping section 72 . When the determining unit 53 determines that the second gripping unit 72 can grip the article P (Yes in step S8), the operation of the article stacking device 10 proceeds to step S9. When the determination unit 53 determines that the article P cannot be gripped by the second gripping unit 72 (No in step S8), the operation of the article stacking device 10 returns to step S6.

In step S9, the second article P2 is gripped by the second gripper 72. As shown in FIG.

At step S10, the parallel link robot 82 picks up the articles P1, P2 and places them on the second conveyor 92. As shown in FIG.

In step S11, the control unit 50 checks whether or not there is an operation stop command. If the operation stop command has been received (Yes in step S11), the control unit 50 stops the operation of the article stacking device 10. FIG. If the operation stop command has not been received (No in step S11), the operation of the article stacking apparatus 10 returns to step S2.

Thus, the operation of the article stacking apparatus 10 is performed.

(5) Comparison with conventional article stacking device (5-1)
Conventionally, as disclosed in Patent Document 1, there has been an article stacking apparatus provided with a gripper having a function of picking up an article being conveyed on one conveyor and moving the article to the other conveyor. Are known.

In the article stacking apparatus disclosed in Patent Document 1, depending on the position of the gripping section, the position of the article, and the posture of the article, there is a risk that the gripping section will interfere with objects existing around the gripping section. . In order to avoid such a situation, the movable range of the grip should be adjusted so that the grip does not interfere with objects regardless of the position or posture of the grip. It is conceivable to set

Further, when the article stacking apparatus has a plurality of gripping sections, the gripping section does not interfere with the object even if the article is gripped by any of the plurality of gripping sections. It is conceivable to set the movable range of the gripping part in consideration of

FIG. 9 shows a boxing device equipped with an article stacking device 10X as an example of a conventional article stacking device. As shown in FIG. 9, the prior art cartoning machine has a safety frame SFX. The article stacking apparatus 10X includes a first conveyor 91X that conveys articles P, and a parallel link robot (not shown) having a header 70X. The first conveyor 91X conveys articles PD and articles PE. The header 70X has a first grip portion 71X and a second grip portion 72X. The first gripping part 71X and the second gripping part 72X must operate without interfering with the safety frame SFX. The dashed-dotted line in FIG. 9 indicates that the gripping portions (here, the first gripping portion 71X and the second gripping portion 72X) are in any position and take any posture, and the gripping portions are attached to the object (here, the safety frame SFX). There is no interference with the object, and no matter which one of the plurality of gripping portions (the first gripping portion 71X and the second gripping portion 72X) grips the article, the gripping portion interferes with the object. This is the movable range of the gripping portion that is set from the viewpoint that there is no need to move. Below, the movable range set based on the above viewpoints is called movable range RM. The article stacking device 10X in which the movable range RM is set cannot grip the article PD or the article PE. This is because, when gripping the article PD or the article PE, part of the gripping portion may not fit within the movable range RM.

Here, depending on the position and attitude of the gripping section, the gripping section of the article stacking device 10X may grip the article PD without contacting the safety frame SFX. For example, as shown in FIG. 9A, the first gripping portion 71X and the second gripping portion 72X, which take a posture whose longitudinal direction is parallel to the transport direction D1, are arranged from the upstream side to the downstream side in the transport direction D1. By approaching the article PD, the first gripping part 71X or the second gripping part 72X can grip the article PD without contacting the safety frame SFX.

Also, the article PE may be safely gripped if it is gripped by the first gripping part 71X. For example, by moving the first gripping portion 71X, whose longitudinal direction is parallel to the conveying direction D1, toward the upstream side from the downstream side in the conveying direction D1, the first gripping portion 71X moves toward the safety frame. The article PE can be gripped without contacting the SFX (see FIG. 9B).

As described above, in the article stacking apparatus 10X according to the related art, since the movable range RM of the gripping section is narrowly restricted, it is possible to grip an article P that may be gripped without interfering with the safety frame SFX. can't For this reason, the efficiency of product stacking is poor.

Alternatively, it is conceivable to widen the installation range of the safety frame SFX in order to increase the movable range RM of the grip portion. However, such measures are not preferable because they may increase the size of the cartoning machine.

(5-2)
On the other hand, in the article stacking apparatus 10 according to the present embodiment, the control section 50 allows the controller 50 to determine whether the outer shape of the gripping portion in plan view or the gripping portion including the article P gripped by the gripping portion in plan view is the safety frame SF. It calculates whether or not the article P is within the interference avoidance range AR in which interference with the article P does not occur, and determines whether or not the article P can be gripped by the parallel link robot 82 . In other words, the article stacking apparatus 10 according to the present embodiment determines whether or not the article P can be gripped depending on whether or not there is a risk of interference with surrounding objects (for example, the safety frame SF) when gripping the article P. do. Therefore, the article stacking apparatus 10 according to the present embodiment can grip the article PD and the article PE shown in FIG. 9 as long as they do not interfere with surrounding objects. Therefore, the efficiency of stacking the articles is higher than when stacking the articles after the movable range RM is determined in advance. Further, the article stacking apparatus 10 according to this embodiment does not increase the size of the apparatus.

(6) Features (6-1)
The article stacking apparatus 10 according to the present embodiment is an article stacking apparatus 10 that moves the conveyed articles P to a stacking position by a parallel link robot 82 and stacks them. The article stacking device 10 includes a first conveyor 91 , a parallel link robot 82 and a controller 50 . The first conveyor 91 conveys articles P. As shown in FIG. The parallel link robot 82 grips the articles P on the conveying surface of the first conveyor 91 and stacks them at the stacking position. The controller 50 controls the operation of the parallel link robot 82 based on the position and orientation of the article P on the conveying surface. The parallel link robot 82 has a plurality of grippers. The multiple gripping portions include a first gripping portion 71 and a second gripping portion 72 that grip the article P. As shown in FIG. When a plurality of gripping units sequentially grip the article P, the control unit 50 determines whether the outline of the gripping units in plan view or the outline of the gripping units including the article P gripped by the gripping units in plan view is equal to the safety frame SF. It calculates whether or not the article P is within the interference avoidance range AR in which interference with the article P does not occur, and determines whether or not the article P can be gripped by the parallel link robot 82 .

In the article stacking apparatus 10 according to the present embodiment, the interference avoidance is such that the outer shape of the gripping portion in plan view or the outer shape of the gripping portion including the article P gripped by the gripping portion in plan view does not interfere with the safety frame SF. The control unit 50 determines whether or not it is within the range AR.

According to this configuration, there is no risk that the gripping portion or the article P gripped by the gripping portion will interfere with the safety frame SF. Further, when the control unit 50 determines that the planar view of the gripping portion or the planar view of the gripping portion including the article P gripped by the gripping portion is within the interference avoidance range AR, the parallel The link robot 82 grips the article P. Therefore, the efficiency of accumulating articles is improved.

(6-2)
In the article stacking apparatus 10 according to the present embodiment, when the first article P1 is the first article P to be gripped by the parallel link robot 82 that is not gripping an article P, the controller 50 controls the parallel link robot 82 It is determined whether or not the first article P1 can be gripped.

In other words, in the article stacking device 10 according to the present embodiment, the outer shape of the first gripping section 71 including the first article P1 gripped by the first gripping section 71, the outer shape of the second gripping section 72, is within the interference avoidance range AR.

According to this configuration, there is no risk that the first gripping portion 71, the second gripping portion 72, or the first article P1 gripped by the first gripping portion 71 will interfere with the safety frame SF. Further, if the outer shape of the first gripping portion 71 including the first article P1 gripped by the first gripping portion 71 and the outer shape of the second gripping portion 72 are within the interference avoidance range AR, the control unit If 50 determines, parallel link robot 82 grips first item P1. Therefore, the efficiency of accumulating articles is improved.

(6-3)
In the article stacking apparatus 10 according to the present embodiment, when the next article P to be gripped by the parallel link robot 82 gripping the first article P1 is set to be the second article P2, the controller 50: Further, it is determined whether or not the parallel link robot 82 can grip the second article P2.

In other words, in the article stacking apparatus 10 according to the present embodiment, the outer shape of the first gripping section 71 including the first article P1 gripped by the first gripping section 71 and the The control unit 50 determines whether or not the outer shape of the second gripping part 72 including the second article P2 placed thereon is within the interference avoidance range AR.

According to this configuration, the first gripping part 71, the second gripping part 72, the first article P1 gripped by the first gripping part 71, or the second article gripped by the second gripping part 72 There is no danger that the article P2 will interfere with the safety frame SF. Also, the outer shape of the first gripping portion 71 including the first article P1 gripped by the first gripping portion 71 and the second gripping portion including the second item P2 gripped by the second gripping portion 72 When the controller 50 determines that the outer shape of the portion 72 is within the interference avoidance range AR, the parallel link robot 82 grips the second article P2. Therefore, the efficiency of accumulating articles is improved.

(6-4)
In the article stacking apparatus 10 according to this embodiment, the first conveyor 91 is provided over the first range R1 and the second range R2. The second range R2 is located downstream of the first range R1 in the conveying direction of the first conveyor 91 . The parallel link robot 82 grips the first article P1 with the first gripper 71 in the first range R1. The parallel link robot 82 grips the second article P2 with the second gripper 72 in the second range R2.

(7) Modifications The above embodiment can be appropriately modified as shown in the following modifications. Each modification may be applied in combination with other modifications as long as there is no contradiction. In addition, the same code|symbol is attached|subjected about the structure similar to said 1st Embodiment, and the detailed description is abbreviate|omitted.

(7-1) Modification A
Although not described in the above embodiment, when the first gripping unit 71 cannot grip the first article P1, the control unit 50 determines whether or not the second gripping unit 72 can grip the first article P1. It may be judged. In this case, the second gripping part 72 may grip the first article P1 in the first range R1. Alternatively, the second gripping part 72 may grip the first article P1 in the second range R2.

Further, when the second gripping section 72 grips the first article P1, the control section 50 may determine whether or not the first gripping section 71 can grip the second article P2. In this case, the first gripping part 71 may grip the second article P2 in the first range R1. Alternatively, the first gripping part 71 may grip the second article P2 in the second range R2.

(7-2) Modification B
Although not described in the above embodiment, when the article P cannot be gripped by the first gripping section 71, the control section 50 determines whether the article P can be gripped by the second gripping section 72 in the second range R2. It may be determined whether When the article P can be gripped by the second gripping section 72, the control section 50 causes the first gripping section 71 to grip an article P other than the article P that can be gripped by the second gripping section 72, and then grips the article P by the second gripping section 72. The second gripping portion 72 may grip the article P that can be gripped by the gripping portion 72 .

(7-3) Modification C
Although not described in the above embodiment, the control unit 50 may determine whether or not to grip the article P according to the angle with respect to the conveying direction in which the article P is conveyed. For example, when the article P is conveyed while being inclined at a predetermined angle or more with respect to the direction parallel to the conveying direction D1, the control section 50 may cancel the grasping by the grasping section.

When the article P is conveyed while being inclined with respect to the direction parallel to the conveying direction D1, it is necessary to rotate the header 70 according to the angle of the article P. As shown in FIG. Here, when the article P is conveyed in a state in which it is inclined at a predetermined angle or more with respect to the direction parallel to the conveying direction D1, it becomes necessary to increase the rotation angle of the header 70 . When the rotation angle of the header 70 is increased, there is a high possibility that the first gripping portion 71 or the second gripping portion 72 will not fit within the interference avoidance range AR.

In the article stacking apparatus 10 according to this modified example, the controller 50 determines whether or not the article P can be gripped according to the angle with respect to the conveying direction in which the article P is conveyed. According to this configuration, when the article P is conveyed in a state inclined at a predetermined angle or more with respect to the direction parallel to the conveying direction, the control unit 50 controls the outer shape of the gripping portion in plan view or the gripping portion It is possible to cancel the gripping of the article P without calculating whether or not the outer shape in plan view of the gripping portion including the gripped article P is within the interference avoidance range AR. Therefore, the calculation speed of the control unit 50 is improved.

(7-4) Modification D
In the above embodiment, the parallel link robot 82 having the first gripping portion 71 and the second gripping portion 72 has been described. However, the configuration of the parallel link robot 82 is not limited to this, and the parallel link robot 82 may have three or more grippers.

(7-5) Modification E
In the above embodiment, the example in which the safety frame SF exists around the plurality of grips has been described. However, the example of the objects existing around the plurality of gripping parts is not limited to this, and the objects may be walls of a factory where the article stacking device 10 is installed, for example.

(7-6) Modification F
In the above embodiment, an example in which the article stacking device 10 includes the parallel link robot 82 has been described. However, the robot provided in the article stacking apparatus 10 is not limited to the parallel link robot 82 . The article stacking apparatus 10 includes a variety of robots as long as they have a plurality of gripping portions that can hold an article P by suction, and are configured to move the plurality of gripping portions to convey the articles P. be able to.

(7-7) Modification G
In the above embodiment, an example of the article stacking device 10 that detects the position and attitude of the article P by the camera 21 has been described. However, the configuration of the article stacking apparatus 10 is not limited to this, and the article stacking apparatus 10 may include a sensor capable of detecting the position and orientation of the article P instead of the camera 21. good.

10 Article stacking device 50 Control unit 71 First gripping unit 72 Second gripping unit 82 Parallel link robot (robot)
91 first conveyor (conveyor)
P Article P1 First article P2 Second article R1 First range R2 Second range

JP 2018-104179 A

Claims (6)

In an article stacking device that moves conveyed articles to a stacking position by a robot and stacks them,
a conveying unit that conveys the article;
a robot that grips the articles on the conveying surface of the conveying unit and stacks them at the stacking position;
a control unit that controls the operation of the robot based on the position and orientation of the article on the conveying surface;
The robot has a plurality of grippers including a first gripper and a second gripper that grip the article,
When the plurality of gripping units sequentially grip the article,
The control unit prevents the outer shape of the gripping portion in plan view or the outer shape of the gripping portion including the article gripped by the gripping portion in plan view from interfering with objects around the plurality of gripping portions. calculating whether or not the object is within an interference avoidance range where the robot does not hold the object, and determining whether or not the object can be grasped by the robot;
Article accumulation device. When the article first gripped by the robot that is not gripping the article is the first article,
The control unit determines whether or not the robot can grip the first item.
2. The article stacking device according to claim 1. When the next item to be gripped by the robot gripping the first item is the second item,
The control unit further determines whether or not the robot can grip the second item.
3. The article stacking device according to claim 2. The transport unit is provided over a first range and a second range located downstream of the first range in the transport direction of the transport unit,
The robot is
gripping the first article by the first gripping part in the first range;
gripping the second article by the second gripping part in the second range;
4. The article stacking device according to claim 3. The control unit determines whether or not the first item can be gripped by the second gripping unit when the first item cannot be gripped by the first gripping unit.
5. The article stacking device according to claim 4. The control unit determines whether or not the article can be gripped according to the angle with respect to the conveying direction in which the article is conveyed.
2. The article stacking device according to claim 1.

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