Gripping device and control method of the same

Abstract

To provide a gripping device and a control method of the same which can improve transportation capability.SOLUTION: A gripping device comprises: a top face gripping part which includes a first adsorption face capable of absorbing a top face of an object; a side face gripping part which includes a second absorption face capable of absorbing a lateral face of the object; and a spring-up mechanism which is switchable between a first state where the side face gripping part is positioned under a lower edge of the top face gripping part and a second state where the side face gripping part is positioned above the lower edge of the top face gripping part.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a gripping device and a method for controlling a gripping device. [Background technology]

[0002] There is known a conveying device such as a palletizing device that stacks articles on trays such as pallets. For example, Patent Document 1 describes a gripping device in the conveying device that grips an article by adsorbing it to the top and sides of the article. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-179338 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the gripping device of Patent Document 1, when no article is being gripped, the angle between the suction surface of the side pad and the suction surface of the upper pad is 93 degrees or more and 135 degrees or less due to the biasing force of the coil spring, and when an article is being gripped, the side pads are attached to the side of the article. In other words, even for lightweight or small articles that do not require support by the side pads, it is necessary to load or unload the article at the four corners while changing the position of the side pads in a plan view in order to avoid interference between other articles and the side pads.

[0005] The present disclosure is devised to solve the above-mentioned problems, and aims to provide a gripping device and a control method for a gripping device that can improve conveying capacity. [Means for solving the problem]

[0006] In order to achieve the above-mentioned objective, a gripping device according to one embodiment of the present disclosure comprises an upper gripping portion having a first suction surface capable of being adsorbed to the upper surface of an article, a side gripping portion having a second suction surface capable of being adsorbed to the side surface of the article, and a flip-up mechanism capable of switching between a first state in which the side gripping portion is positioned below a lower end of the upper gripping portion and a second state in which the side gripping portion is positioned above the lower end of the upper gripping portion.

[0007] In order to achieve the above-mentioned object, a control method for a gripping device according to one embodiment of the present disclosure includes a transport target data acquisition step of acquiring transport target data indicating data regarding an item to be transported by the gripping device, an image data acquisition step of acquiring image data of an item to be unloaded or a predetermined area including an area in which the items are to be loaded, a judgment step of determining whether or not side gripping of the item by the side gripping unit is necessary to transport the item based on the transport target data, a switching step of switching the side gripping unit to the second state if it is determined in the judgment step that side gripping is not necessary, and a transport step of supporting the item with at least the upper gripping unit and transporting it. Effect of the Invention

[0008] According to the present disclosure, it is possible to obtain the effect of improving the transport capacity. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram of a gripping device according to the present embodiment. [Diagram 2] FIG. 2 is a schematic diagram showing a state in which the gripping device shown in FIG. 1 is flipped up by 90 degrees. [Diagram 3] FIG. 3 is a schematic diagram showing a 180° flip-up state of the gripping device shown in FIG. [Figure 4] FIG. 4 is a schematic block diagram of the gripping device shown in FIG. [Diagram 5] FIG. 5 is a flowchart illustrating a process flow of the control device. [Figure 6]FIG. 6 is a plan view for explaining a typical unloading operation by the gripping device. [Figure 7] FIG. 7 is a cross-sectional view taken along the line II-II shown in FIG. [Figure 8] FIG. 8 is a cross-sectional view showing the state after FIG. [Figure 9] FIG. 9 is a plan view for explaining a schematic unloading operation by the gripping device of the comparative example. [Figure 10] FIG. 10 is a cross-sectional view taken along the line II-II shown in FIG. [Figure 11] FIG. 11 is a plan view for explaining a typical unloading operation by the gripping device of the comparative example. [Figure 12] FIG. 12 is a cross-sectional view taken along the line II-II shown in FIG.

[0010] (Embodiment) Hereinafter, the embodiments according to the present disclosure will be described in detail with reference to the drawings. Note that the present invention is not limited to these embodiments. In addition, the components in the following embodiments include those that are replaceable and easy for a person skilled in the art, those that are substantially the same, or those that are equivalent. Furthermore, the components in the following embodiments can be omitted, replaced, or modified in various ways without departing from the gist of the present disclosure. In the following embodiments, the components necessary for illustrating the embodiments will be described, and other components will be omitted, and the same components will be given the same reference numerals, and different components will be given different reference numerals.

[0011] Fig. 1 is a schematic diagram of a gripping device according to this embodiment. Fig. 2 is a schematic diagram showing a 90° flip-up mode of the gripping device shown in Fig. 1. Fig. 3 is a schematic diagram showing a 180° flip-up mode of the gripping device shown in Fig. 1. Fig. 4 is a schematic block diagram of the gripping device shown in Fig. 1. The gripping device 1 shown in Figs. 1 to 4 is attached to a palletizing device as a conveying device, and is a device for stacking articles on a pallet, unloading articles from a pallet, or transferring articles from one pallet to another pallet in a facility where logistics is managed, such as a warehouse.

[0012] Here, the definition of a pallet by the Japan Pallet Association is "a surface on which cargo is placed in a single unit, and has a structure that allows loading, transporting, and storage all by hand or by a dedicated vehicle such as a forklift, including those with a superstructure." In this embodiment, a pallet refers to a container or platform on which the goods R are loaded. In other words, the pallet referred to here is not limited to a so-called flat platform, but may also include a basket cart or the like, and may be of any shape. The goods R are loaded onto the pallet, such as goods to be shipped. The goods R are also referred to as cardboard boxes in which goods are packed. The goods R have at least a flat top surface, and in this embodiment, a rectangular cardboard box is assumed.

[0013] 1 to 3, the gripping device 1 includes a base 10, an upper gripping unit 20, a side gripping unit 30, a first arm 40, a second arm 50, and a flip-up mechanism 60. As shown in Fig. 4, the gripping device 1 further includes an imaging device 70, an input / output device 80, and a control device 90 that controls the operation of each part of the gripping device 1. In this embodiment, the gripping device 1 including the imaging device 70, the input / output device 80, and the control device 90 includes a mode in which the functions of each of the devices are configured as part of the functions of a palletizing device to which the gripping device 1 is attached or a conveying system to which the palletizing device is deployed.

[0014] In this embodiment, the X-axis direction is a direction perpendicular to the second opposing surface 30a that faces the side surface of the article R when the side gripping part 30 supports the side surface of the article R, the Y-axis direction is a direction parallel to the rotation axis A of the flip-up mechanism 60, and the Z-axis direction is a direction perpendicular to the X-axis and Y-axis directions and perpendicular to the first opposing surface 20a that faces the upper surface of the article R when the upper surface gripping part 20 supports the upper surface of the article R. At least during operation of the gripping device 1, the X-axis and Y-axis directions correspond to the horizontal direction, and the Z-axis direction corresponds to the vertical direction.

[0015] 1 to 3 is connected to the tip of the arm of the palletizing device to which the gripping device 1 is attached via a rotating shaft 12, a rotating mechanism 14, and a lifting mechanism 16. The rotating shaft 12 is fixed to the upper surface side of the base 10 so that its axis is parallel to the Z-axis direction. The base 10 and the rotating shaft 12 are supported rotatably in a rotational direction φ around the axis of the rotating shaft 12 with respect to the arm of the palletizing device.

[0016] The turning mechanism 14 shown in Fig. 4 turns the base 10 and the turning shaft 12 in a rotation direction φ. For example, if the palletizing device is a multi-joint robot, the turning of the turning shaft 12 by the turning mechanism 14 corresponds to the operation of the sixth axis of the multi-joint robot. The turning mechanism 14 is realized by a well-known mechanism such as a rotary actuator including a motor, a rack-and-pinion mechanism including an air cylinder, or a wire or link mechanism. The operation of the turning mechanism 14 is controlled by a control unit 96 of the control device 90.

[0017] The lifting mechanism 16 linearly moves the base 10 and the rotating shaft 12 in a vertical direction V parallel to the Z-axis direction. For example, if the palletizing device is a multi-joint robot, the linear movement of the rotating shaft 12 by the lifting mechanism 16 is achieved by the cooperative operation of multiple axes of the multi-joint robot. If the palletizing device is a Cartesian coordinate robot, the linear movement of the rotating shaft 12 by the lifting mechanism 16 corresponds to the operation of a vertical linear joint of the Cartesian coordinate robot. In this case, the lifting mechanism 16 is achieved by a well-known mechanism such as a linear actuator including a motor, an air cylinder, etc., or a rack and pinion mechanism. The operation of the lifting mechanism 16 is controlled by a control unit 96 of the control device 90.

[0018] The upper gripping part 20 is provided on the lower part of the base 10. The upper gripping part 20 has a first opposing surface 20a on its lower surface that faces the upper surface of the article R. The upper gripping part 20 is fixed to the base 10 so that the first opposing surface 20a is perpendicular to the Z-axis direction. The upper gripping part 20 moves up and down and rotates in accordance with the lifting and rotating movements of the base 10 and the rotating shaft part 12. The upper gripping part 20 has a first suction part 22 on the first opposing surface 20a that is capable of suctioning the article R.

[0019] The first suction unit 22 is depicted in the form of a single block in the examples shown in Figs. 1 to 3, but may be, for example, a plurality of suction pads protruding downward from the first opposing surface 20a of the upper gripping unit 20. The first suction unit 22 has a first suction surface 22a at its lower end. When the first suction surface 22a is in contact with the upper surface of the article R, the first suction unit 22 is attracted to the upper surface of the article R by the operation of the first suction mechanism 24 shown in Fig. 4. The first suction mechanism 24 includes, for example, a vacuum generator connected to the first suction surface 22a via an air pipe (not shown) and sucking air from the first suction surface 22a. For example, when the first suction unit 22 is composed of a plurality of suction pads, each suction pad is connected to the first suction mechanism 24, which is a vacuum generator, via an air pipe. The operation of the first suction mechanism 24 is controlled by the control unit 96 of the control device 90.

[0020] The side gripping part 30 is provided on the side of the base 10 in the X-axis direction via the first arm 40, the second arm 50, and the flip-up mechanism 60. The side gripping part 30 has a second opposing surface 30a that faces the side surface of the article R. The side gripping part 30 can move in the longitudinal direction of the first arm 40 relative to the base 10 by a first telescopic mechanism 44 described later. The side gripping part 30 can also move in the longitudinal direction of the second arm 50 relative to the base 10 by a second telescopic mechanism 54 described later. The side gripping part 30 can also rotate in a rotation direction θ around a rotation axis A of the flip-up mechanism 60 relative to the base 10 by the flip-up mechanism 60. The rotation axis A is a horizontal axis parallel to both the first suction surface 22a of the upper gripping part 20 and the second suction surface 32a of the side gripping part 30.

[0021] The side gripping part 30 can move relative to the top gripping part 20 in the XZ plane by the first telescopic mechanism 44, the second telescopic mechanism 54, and the flip-up mechanism 60. In other words, the first telescopic mechanism 44 and the second telescopic mechanism 54 are moving mechanisms that move the side gripping part 30 relative to the top gripping part 20. The side gripping part 30 of this embodiment does not move relative to the top gripping part 20 in the Y-axis direction, but may be configured to be relatively movable in the Y-axis direction. The side gripping part 30 has a second suction part 32 that can suction the article R on the second opposing surface 30a.

[0022] The second suction unit 32 is depicted as a single block shape in the examples shown in Figs. 1 to 3, but may be, for example, a plurality of suction pads protruding from the second opposing surface 30a of the side gripping unit 30. The second suction unit 32 has a second suction surface 32a at an end opposite to the second opposing surface 30a. When the second suction surface 32a is in contact with the side surface of the article R, the second suction unit 32 is suctioned to the side surface of the article R by the operation of the second suction mechanism 34 shown in Fig. 4. The second suction mechanism 34 includes, for example, a vacuum generator connected to the second suction surface 32a via an air pipe (not shown) and sucking air from the second suction surface 32a. For example, when the second suction unit 32 is composed of a plurality of suction pads, each suction pad is connected to the second suction mechanism 34, which is a vacuum generator, via an air pipe. The operation of the second suction mechanism 34 is controlled by the control unit 96 of the control device 90.

[0023] In the state shown in FIG. 1 where the longitudinal direction of the first arm 40 is parallel to the X-axis direction and the longitudinal direction of the second arm 50 is parallel to the Z-axis direction, the second opposing surface 30a of the side gripping portion 30 faces the side surface of the article R. In this case, the second suction surface 32a of the second suction portion 32 faces the side surface of the article R. Also, in this case, the entire surface of the second suction surface 32a is located below the first suction surface 22a. In the state shown in FIG. 2 where the longitudinal direction of the first arm 40 is parallel to the Z-axis direction and the longitudinal direction of the second arm 50 is parallel to the X-axis direction, the second opposing surface 30a faces vertically downward. In this case, the second suction surface 32a of the second suction portion 32 faces vertically downward. Also, in this case, the second suction surface 32a is located above the first suction surface 22a by a distance B.

[0024] The first arm 40 is provided on the side of the base 10 in the X-axis direction via the second arm 50 and the flip-up mechanism 60. The first arm 40 has a first support 42 and a first telescopic mechanism 44. The first support 42 is located at one end side of the longitudinal direction of the first arm 40. The first support 42 is connected to the second arm 50. The first support 42 supports the first telescopic mechanism 44 and is connected to the side gripping part 30 via the first telescopic mechanism 44. In this embodiment, the first support 42 has a frame shape that houses and supports the first fixed part 44a of the first telescopic mechanism 44. The first telescopic mechanism 44 extends along the longitudinal direction of the first arm 40 and is telescopic in a first telescopic direction F1, which is the longitudinal direction of the first arm 40. The first telescopic mechanism 44 is pre-extended and retracted to match the width dimension w of the article R so that the second suction surface 32a abuts against the side of the article R in the state shown in Figure 1, where the longitudinal direction of the first arm 40 is parallel to the X-axis direction and the longitudinal direction of the second arm 50 is parallel to the Z-axis direction.

[0025] In this embodiment, the first telescopic mechanism 44 includes a first fixed part 44a and a first movable part 44b. The first fixed part 44a is fixed to the first support part 42. The first fixed part 44a supports the first movable part 44b so that the first movable part 44b can move linearly in the first telescopic direction F1 within a predetermined range. The first movable part 44b can move in the first telescopic direction F1 relative to the first fixed part 44a. One end side of the first movable part 44b in the longitudinal direction is supported by the first fixed part 44a. The other end side of the first movable part 44b in the longitudinal direction is fixed to the side grip part 30. The first telescopic mechanism 44 is realized by a well-known mechanism such as a cylinder having a cylindrical first fixed part 44a and a rod-shaped first movable part 44b, an electric actuator, a wire, or a link mechanism.

[0026] The second arm 50 is provided on the side of the base 10 in the X-axis direction via the flip-up mechanism 60. The second arm 50 has a second support 52 and a second telescopic mechanism 54. The second support 52 is located at one end of the second arm 50 in the longitudinal direction. The second support 52 is connected to the flip-up mechanism 60. The second support 52 supports the second telescopic mechanism 54 and is connected to the first support 42 of the first arm 40 via the second telescopic mechanism 54. In this embodiment, the second support 52 has a frame shape that accommodates and supports the second fixed portion 54a of the second telescopic mechanism 54. The second telescopic mechanism 54 extends along the longitudinal direction of the second arm 50 and is telescopic in a second telescopic direction F2, which is the longitudinal direction of the second arm 50. The second telescopic mechanism 54 is pre-extended and retracted to match the height dimension h of the article R so that the second suction surface 32a abuts at a suitable height position on the side of the article R in the state shown in Figure 1, where the longitudinal direction of the first arm 40 is parallel to the X-axis direction and the longitudinal direction of the second arm 50 is parallel to the Z-axis direction.

[0027] In this embodiment, the second telescopic mechanism 54 includes a second fixed part 54a and a second movable part 54b. The second fixed part 54a is fixed to the second support part 52. The second fixed part 54a supports the second movable part 54b so that the second movable part 54b can move linearly in the second telescopic direction F2 within a predetermined range. The second movable part 54b can move in the second telescopic direction F2 relative to the second fixed part 54a. One end side of the second movable part 54b in the longitudinal direction is supported by the second fixed part 54a. The other end side of the second movable part 54b in the longitudinal direction is fixed to the first support part 42 of the first arm part 40. The second telescopic mechanism 54 is realized by a well-known mechanism such as a cylinder having a cylindrical second fixed part 54a and a rod-shaped second movable part 54b, an electric actuator, a wire, or a link mechanism.

[0028] The flip-up mechanism 60 can be switched between a first state (a state shown in FIG. 1) in which the side gripping portion 30 is positioned below the lower end of the upper gripping portion 20 (in this embodiment, the first suction surface 22a of the first suction portion 22) and a second state (a state shown in FIGS. 2 and 3) in which the side gripping portion 30 is positioned above the lower end of the upper gripping portion 20. The flip-up mechanism 60 is connected to the upper gripping portion 20 via the base 10. The flip-up mechanism 60 is also connected to the side gripping portion 30 via the first arm portion 40 and the second arm portion 50. The flip-up mechanism 60 of this embodiment is provided on the side of the base 10 in the X-axis direction. The flip-up mechanism 60 rotates the second arm portion 50, the first arm portion 40, and the side gripping portion 30 relative to the base 10 in a rotation direction θ around a rotation axis A parallel to the Y-axis direction.

[0029] In this embodiment, the flip-up mechanism 60 has a fixed part 62 and a rotating part 64. The fixed part 62 is fixed to the connecting part 10a of the base 10. That is, the fixed part 62 moves integrally with the base 10 and the upper grip part 20. The rotating part 64 is rotatable in a rotation direction θ around a rotation axis A relative to the fixed part 62. The rotating part 64 is fixed to the second support part 52 of the second arm part 50. The flip-up mechanism 60 is realized by a well-known mechanism such as a rotary actuator including a motor, a rack and pinion mechanism including an air cylinder, a wire or link mechanism, etc. The flip-up mechanism 60 has a lock mechanism (not shown) that can position the position of the rotation direction θ of the rotating part 64 relative to the fixed part 62. The lock mechanism is realized by a well-known mechanism such as an air lock using high-pressure air, a mechanical lock using a motor drive, or a solenoid lock using an electromagnetic solenoid.

[0030] The flip-up mechanism 60 allows the side gripping part 30, the first arm 40, and the second arm 50 to rotate in a rotation direction θ around the rotation axis A between the 0° position shown in FIG. 1, the 90° position shown in FIG. 2, and the 180° position shown in FIG. 3. In addition, the side gripping part 30, the first arm 40, and the second arm 50 can be positioned at any position between the 0° position shown in FIG. 1 and the 180° position shown in FIG. 3 by a locking mechanism (not shown). In the 0° position shown in FIG. 1, the first arm 40 is located lower than the second arm 50, and the second suction surface 32a of the side gripping part 30 is located lower than the first suction surface 22a of the upper gripping part 20 and faces the side of the article R. In the 90° position shown in FIG. 2, the second suction surface 32a of the side gripping part 30 faces vertically downward and is located above the first suction surface 22a of the upper gripping part 20 by a distance B. At the 180° position shown in FIG. 3, the second suction surface 32a of the side gripping portion 30 faces the X-axis direction opposite to the base portion 10, and the first arm portion 40 is positioned above the second arm portion 50.

[0031] The imaging device 70 captures images of a pallet on which the article R is to be loaded or unloaded, the article R loaded on the pallet, and the stacked arrangement of the articles R, and outputs image data that can identify the position and individual objects of the imaged objects to the control device 90. The imaging device 70 is disposed in a position where the pallet and the article R loaded on the pallet can be observed. The imaging device 70 includes one or more cameras.

[0032] The input / output device 80 includes an input device through which an operator inputs various pieces of information for operating the gripping device 1, and an output device for presenting various pieces of information to the operator. The input device is realized by, for example, a keyboard, a mouse, a physical switch, a button, a touch panel, or the like. The output device is realized by, for example, a display device including a liquid crystal display device, an organic EL (Electro Luminescence) display device, or the like, a light-emitting device including an LED (Light Emitting Diode), or a speaker, or the like. The input / output device 80 may be an information terminal capable of inputting and outputting various pieces of information.

[0033] The control device 90 is a computer that controls the gripping device 1. The control device 90 has a communication unit 92, a storage unit 94, and a control unit 96. The communication unit 92 is a module used by the control unit 96 to communicate with an external device such as the management device 100, and may include, for example, an antenna. In this embodiment, the communication method by the communication unit 92 is assumed to be wireless communication, but the communication method may be arbitrary. The storage unit 94 is a memory that stores the calculation contents and programs of the control unit 96, and various information acquired from the management device 100 via the communication unit 92, and includes, for example, at least one of a RAM (Random Access Memory), a main storage device such as a ROM (Read Only Memory), and an external storage device such as an HDD (Hard Disk Drive).

[0034] The control unit 96 is an arithmetic processing device, and includes an arithmetic circuit such as a CPU (Central Processing Unit). The control unit 96 executes various processes by reading and executing programs (software) from the storage unit 94. The control unit 96 may execute processes using one CPU, or may be provided with multiple CPUs and execute processes using the multiple CPUs.

[0035] The control unit 96 acquires upstream data from the management device 100 via the communication unit 92. The upstream data includes, for example, the type, weight, dimensions, perforations of the boxes, the number of glued items, the number of items R, the arrangement of each item R on the pallet or the position where the items R are stacked on the pallet, the order in which the items R are unloaded from the pallet or the order in which they are stacked on the pallet, and other transport target data. The control unit 96 executes imaging by the imaging device 70 at any timing and acquires image data. The control unit 96 processes the acquired image data to recognize the number, position, shape, size, and the like of the items R present in the image data. The control unit 96 determines whether or not the side gripping unit 30 needs to grip the side and the direction and angle of the side gripping unit 30 to flip up based on the image data and the transport target data. The control unit 96 controls the swivel mechanism 14, the lifting mechanism 16, the first suction mechanism 24, the second suction mechanism 34, the first telescopic mechanism 44, the second telescopic mechanism 54, and the flip-up mechanism 60 based on the determined content and the transport target data. The control unit 96 also executes control for moving the gripping device 1 itself in the horizontal direction in the palletizing device to which the gripping device 1 is attached. When the palletizing device is a multi-joint robot, the horizontal movement of the gripping device 1 itself is realized by the cooperative operation of multiple axes of the multi-joint robot.

[0036] The management device 100 is a system that manages the operation of each device in a logistics management facility in which the gripping device 1 of this embodiment is deployed. The management device 100 is, for example, a warehouse control system (WCS) or a warehouse management system (WMS), but is not limited to a WCS or a WMS and may be any system, for example, a back-end system such as other production management systems. The location at which the management device 100 is installed is arbitrary, and it may be installed in the facility in which the gripping device 1 is deployed, or may be installed at a location remote from the facility to manage the facility from the remote location.

[0037] (Control unit processing) Next, a process flow for determining whether or not side gripping is required by the side gripping unit 30 during transportation by the gripping device 1 will be described. Here, a case in which a plurality of items R stacked on a pallet is unloaded will be described. FIG. 5 is a flowchart illustrating the process flow of the control device. The process shown in FIG. 5 is executed by the control unit 96 of the control device 90 based on programs and data previously stored in the memory unit 94. For example, by receiving a predetermined control signal from the management device 100 instructing the driving of the gripping device 1, the control device 90 proceeds to step S10 shown in FIG. 5 and starts the process.

[0038] The control device 90 acquires the transport target data (step S10). In this embodiment, the control device 90 acquires the transport target data from the management device 100 via the communication unit 92. In this process, the transport target data includes at least data that serves as a basis for determining whether or not side gripping by the side gripping unit 30 is necessary when lifting each item R to be unloaded by the gripping device 1. For example, if the item R is small and light, side gripping is not necessary. The transport target data also includes data indicating the number and position (coordinates on the pallet) of each item R to be unloaded, and the order of unloading.

[0039] The control device 90 sets the number of executions i to i=1 and starts the loop process (step S12). In the loop process, while i≦n is satisfied, the processes from step S14 to step S20 are repeatedly executed n times. Here, n is the number of items R loaded on the pallet, and i indicates the order in which the items R are unloaded from the pallet.

[0040] The control device 90 acquires captured image data (step S14). In this embodiment, the control device 90 causes the imaging device 70 to capture an image of a predetermined area including the i-th item R to be unloaded. The imaging device 70 outputs captured image data indicating data of the captured image to the control device 90. The captured image data may be linked to coordinate data of a coordinate system based on a predetermined position of the gripping device 1 or the facility in which the gripping device 1 is deployed, for example. The control device 90 performs image processing on the captured image data to recognize the position, shape, size, etc. of the i-th item R to be unloaded.

[0041] The control device 90 determines whether side gripping is necessary (step S16). In this embodiment, the control device 90 determines whether side gripping is necessary based on the transport target data acquired in step S10. For example, if the i-th item R to be unloaded can be sufficiently lifted by the upper gripping unit 20 alone, it is determined that side gripping is unnecessary. If the control device 90 determines that side gripping is necessary (step S16; Yes), it proceeds to step S20. If the control device 90 determines that side gripping is not necessary (step S16; No), it proceeds to step S18.

[0042] When the control device 90 judges that side gripping is not necessary (step S16; No), it determines the flip-up direction and angle of the side gripping part 30 based on the captured image data acquired in step S14 (step S18). The flip-up direction indicates the position of the side gripping part 30 in the φ rotation direction. The flip-up angle indicates the position of the side gripping part 30 in the θ rotation direction. If there is an obstacle around the i-th item R to be unloaded, the side gripping part 30 may interfere with the obstacle. Specifically, if another item R is loaded adjacent to the side gripping part 30 side of the item R (the right side shown in FIG. 1), the side gripping part 30 may interfere with the adjacent item R when the upper gripping part 20 abuts against the upper surface of the item R.

[0043] The positions of the side gripping portion 30 in the θ rotation direction and the φ rotation direction at the start of step S16 are, for example, the positions of the side gripping portion 30 when the (i-1)th item R is unloaded. In step S18, the control device 90 first acquires the position of the side gripping portion 30 in the φ rotation direction. The control device 90 then determines whether or not there is another item R that would be an obstacle in the direction of the side gripping portion 30 relative to the i-th item R, based on the captured image data acquired in step S14. If the control device 90 determines that there is no other item R that would be an obstacle, it decides to maintain the flip-up direction and angle of the side gripping portion 30, and proceeds to step S20.

[0044] When the control device 90 determines that there is another object R that is an obstacle, it determines the flip-up angle of the side gripping unit 30 so that the side gripping unit 30 can avoid the obstacle. When the control device 90 determines, for example, based on at least one of the transport object data and the captured image data, that the height dimension h of the other object R that is an obstacle is equal to or smaller than the height dimension h of the i-th object R, it determines the flip-up angle to be 90° (the position shown in FIG. 2). When the control device 90 determines, for example, based on at least one of the transport object data and the captured image data, that the height dimension h of the other object R that is an obstacle is greater than the height dimension h of the i-th object R and is smaller than a predetermined threshold, it determines the flip-up angle to be 180° (the position shown in FIG. 3). The predetermined threshold is set in advance by the configuration of the gripping device 1 other than the side gripping unit 30. For example, in the configuration of this embodiment, the predetermined threshold is set within a range where the second support unit 52 does not interfere at the 180° position shown in FIG. 3.

[0045] When the control device 90 determines, for example, based on at least one of the transport target data and the captured image data, that the height dimension h of the other obstructing object R is equal to or greater than a predetermined threshold, it decides to move the side gripping unit 30 in the φ rotation direction. The control device 90 determines, in the above-mentioned procedure, a flip-up angle at which the side gripping unit 30 can avoid the other obstructing object R when the side gripping unit 30 has moved 90°, 180°, or 270° in the φ rotation direction. After determining the flip-up direction and angle of the side gripping unit 30, the control device 90 proceeds to step S20.

[0046] The control device 90 transports (unloads) the i-th article R (step S20). The control device 90 first controls the swivel mechanism 14 and the flip-up mechanism 60 according to the flip-up direction and angle determined in step S18, and positions the side gripping unit 30 in a predetermined posture. When side gripping is performed by the side gripping unit 30, the control device 90 controls the first telescopic mechanism 44 and the second telescopic mechanism 54 to extend and retract the first arm 40 and the second arm 50 based on the width dimension w of the i-th article R (see FIG. 1) so that the side gripping unit 30 is positioned at a suitable position on the side of the article R.

[0047] Next, the control device 90 controls the gripping device 1 to move horizontally to a position where the first suction portion 22 of the upper gripping portion 20 faces the upper surface of the article R. Next, the control device 90 controls the lifting mechanism 16 to lower the base 10 and the upper gripping portion 20 to a position where the first suction surface 22a of the first suction portion 22 abuts against the upper surface of the article R. Next, the control device 90 operates the first suction mechanism 24 to suction the upper surface of the article R to the first suction surface 22a. If it is determined in step S16 that side gripping is necessary, the control device 90 operates the second suction mechanism 34 to suction the side of the article R to the second suction surface 32a. As a result, the gripping device 1 supports the article R. The control device 90 uses the lifting mechanism 16 to raise the gripping device 1 gripping the article R, transports it to a predetermined position, and unloads the i-th article R from the pallet.

[0048] The control device 90 resets the execution number i in the loop process as i=i+1, and returns to step S14 (step S22). When the process from step S14 to step S20 is executed n times and the unloading of n items R on the pallet is completed, the loop process ends.

[0049] 5, step S14 was performed for each item R, but for example, when the items R are arranged in a plane on the pallet, i.e., when multiple items R are not stacked vertically, step S14 of imaging all the items R on the pallet may be performed only once at the beginning. Also, in the process of this embodiment, the number and position (coordinate) data of each item R are included in the transport target data, but the number and positions of the items R may be obtained based on captured image data of all the items R on the pallet.

[0050] In addition, although the above description has been given of the process of unloading the article R from a pallet on which multiple articles R are loaded, the process of this embodiment shown in Fig. 5 can also be applied to the case of loading multiple articles R onto a pallet. In this case, in step S14, an image of a predetermined area including an area on the pallet where the article R is to be loaded is captured. In addition, in step S18, when loading the i-th article R at a predetermined position on the pallet, the direction and angle of the bounce are determined based on the presence or absence and size of an obstacle in an area adjacent to the area where the article R is to be loaded. In this case, the obstacle is the 1st to i-1th articles R loaded.

[0051] (Unloading operation) FIG. 6 is a plan view for explaining the unloading operation by the gripping device. FIG. 7 is a cross-sectional view taken along the line II-II shown in FIG. 6. FIG. 8 is a cross-sectional view showing the state after FIG. 7. FIGS. 6 to 8 show the operation of unloading the item R4 among the items R1, R2, R3, and R4 arranged on the pallet P. The items R1, R2, R3, and R4 all have the same dimensions. The item R4 is arranged adjacent to the item R3 on the left side in the plan view shown in FIG. 6. Also, in FIGS. 6 to 8, only the upper gripping portion 20 and the side gripping portion 30 of the gripping device 1 are depicted. Also, the side gripping portion 30 is assumed to be in the 90° position shown in FIG. 2.

[0052] 6 and 7, with the first suction portion 22 of the top gripping portion 20 in contact with the top surface of the article R4, the side gripping portion 30 is positioned above the article R3. At this time, the lower end of the second suction portion 32 of the side gripping portion 30 is positioned a distance B above the lower end of the first suction portion 22 (see FIG. 2). Therefore, the second suction portion 32 of the side gripping portion 30 does not come into contact with the article R3. As shown in FIG. 8, the gripping device 1 of this embodiment can unload the article R4 only by suction with the first suction portion 22 of the top gripping portion 20.

[0053] (Conventional unloading operation) 9 and 11 are plan views for explaining the unloading operation by the gripping device of the comparative example. FIG. 10 is a cross-sectional view taken along the line II-II shown in FIG. 9. FIG. 12 is a cross-sectional view taken along the line II-II shown in FIG. 11. FIGS. 9 to 12 show the operation of unloading the item R4, among the items R1, R2, R3, and R4 arranged on the pallet P, by the gripping device of the comparative example. The items R1, R2, R3, and R4 all have the same dimensions. The item R4 is arranged adjacent to the item R3 on the left side in the plan views shown in FIGS. 9 and 11. Also, in FIGS. 9 to 12, only the upper gripping portion 20 and the side gripping portion 30A of the gripping device of the comparative example are depicted. The side gripping portion 30A of the comparative example is equivalent to the state in which the side gripping portion 30 of the present embodiment is fixed at the 0° position shown in FIG. 1.

[0054] As shown in Fig. 9 and Fig. 10, in the gripping device of the comparative example, when the upper gripping part 20 and the side gripping part 30A are lowered to bring the first suction part 22 of the upper gripping part 20 into contact with the upper surface of the article R4, the side gripping part 30A collides with the upper surface of the article R3. Therefore, as shown in Fig. 11 and Fig. 12, the upper gripping part 20 and the side gripping part 30A are rotated 180° in the φ rotation direction (see Fig. 1) to move the side gripping part 30A away from the position above the article R3. As a result, as shown in Fig. 12, the upper gripping part 20 and the side gripping part 30A can be lowered to a position where the first suction part 22 of the upper gripping part 20 comes into contact with the upper surface of the article R4. That is, in the gripping device of the comparative example, the means for avoiding interference between the side gripping part 30A and an obstacle is limited to rotating the upper gripping part 20 and the side gripping part 30A in the φ rotation direction (see FIG. 1).

[0055] (Effects of the embodiment) The gripping device 1 and the control method of the gripping device 1 described in the embodiment can be understood, for example, as follows.

[0056] The gripping device 1 of the first embodiment comprises an upper gripping portion 20 having a first suction surface 22a capable of being adsorbed to the upper surface of an article R, a side gripping portion 30 having a second suction surface 32a capable of being adsorbed to the side surface of the article R, and a flip-up mechanism 60 capable of switching between a first state in which the side gripping portion 30 is positioned below the lower end of the upper gripping portion 20, and a second state in which the side gripping portion 30 is positioned above the lower end of the upper gripping portion 20.

[0057] In the gripping device 1 according to the first embodiment, the side gripping portion 30 is positioned above the lower end of the upper gripping portion 20 in the second state, so that an article R that does not require support by the side gripping portion 30, such as a lightweight article R or a small article R, can be lifted by the upper gripping portion 20 alone. When stacking a plurality of articles R on a pallet, unloading an article R from a pallet on which a plurality of articles R are stacked, or transferring an article R from an arbitrary pallet to another pallet, other articles R stacked around the article R to be transported may become an obstacle. However, when the side gripping portion 30 is in the second state, it is positioned above the lower end of the upper gripping portion 20, i.e., it is positioned above the upper surface of the article R, so that interference with an obstacle at least equal to or lower in height to the article R can be avoided. By switching the state of the side gripping portion 30, interference between other items R and the side gripping portion 30 can be avoided, so there is no need to load or unload items at the four corners while changing the position of the side gripping portion 30 in a planar view, as was done in the past, thereby improving transport capacity.

[0058] The gripping device 1 in the second embodiment includes a first suction mechanism 24 that activates suction at the first suction surface 22a when the first suction surface 22a is in contact with the upper surface of the article R, and a second suction mechanism 34 that activates suction at the second suction surface 32a when the second suction surface 32a is in contact with the side surface of the article R.

[0059] The gripping device 1 according to the second aspect can operate the first suction mechanism 24 and the second suction mechanism 34 separately, and therefore can separately control the suction operation by the upper gripping part 20 and the suction operation by the side gripping part 30. That is, when the article R is transported only by the upper gripping part 20, the second suction mechanism 34 can be stopped when the side gripping part 30 is in the second state.

[0060] In the gripping device 1 according to the third embodiment, the flip-up mechanism 60 has a locking mechanism that positions the side gripping portion 30 at the position of the second state.

[0061] In the gripping device 1 according to the third aspect, when the article R is transported only by the upper gripping part 20, the position of the side gripping part 30 can be fixed when the side gripping part 30 is in the second state, so that the side gripping part 30 can be prevented from unintentionally descending to the position of the first state or swinging. This makes it possible to stably avoid interference between other articles R and the side gripping part 30, so that the article R can be transported stably.

[0062] In the gripping device 1 of the fourth aspect, the flip-up mechanism 60 rotates the side gripping portion 30 around a first rotation axis (rotation axis A) that is parallel to the first suction surface 22a and the second suction surface 32a and is positioned above the side gripping portion 30 in the first state.

[0063] The gripping device 1 according to the fourth embodiment can switch the side gripping part 30 between a first state and a second state by rotating the side gripping part 30 about a first rotation axis relative to the upper gripping part 20. Therefore, the flip-up mechanism 60 can be realized by a well-known simple configuration such as a motor with the first rotation axis as its axis or a rack-and-pinion mechanism.

[0064] The gripping device 1 of the fifth aspect comprises a first arm 40 having one end connected to the side gripping portion 30 and capable of expanding and contracting in a first direction (first expansion / contraction direction F1) perpendicular to the second suction surface 32a, and a second arm 50 having one end connected to the other end of the first arm 40 and the other end connected to the top gripping portion 20 via a flip-up mechanism 60, and capable of expanding and contracting in a second direction (second expansion / contraction direction F2) parallel to the second suction surface 32a and perpendicular to the first rotation axis (rotation axis A).

[0065] In the gripping device 1 according to the fifth aspect, when side gripping by the side gripping part 30 is required, the position of the side gripping part 30 can be adjusted with respect to the position of the upper gripping part 20 supporting the upper surface of the article R in accordance with the dimensions of the article R. That is, when the upper gripping part 20 adsorbs the center of the upper surface of the article R, the first arm 40 can be extended and contracted so that the second suction surface 32a abuts against the side surface of the article R, so that it is possible to accommodate changes in the width dimension w of the article R. Also, in order to more suitably support the side surface of the article R with the side gripping part 30, the second arm 50 can be extended and contracted so as to change the height position of the second suction surface 32a, so that it is possible to accommodate changes in the height dimension h of the article R.

[0066] In the gripping device 1 according to the sixth embodiment, the flip-up mechanism 60 translates the side gripping part 30 in a direction perpendicular to the first suction surface 22a.

[0067] The gripping device 1 according to the sixth aspect can switch the side gripping part 30 between the first state and the second state by translating the side gripping part 30 in a direction perpendicular to the first suction surface 22a relative to the upper gripping part 20. Therefore, the flip-up mechanism 60 can be realized with a well-known simple configuration such as a linear actuator including a motor or an air cylinder, a rack-and-pinion mechanism, a wire or link mechanism, or the like.

[0068] The gripping device 1 according to the seventh embodiment includes a rotation mechanism that rotates the upper gripping part 20 and the side gripping part 30 about a vertical second rotation axis.

[0069] The gripping device 1 according to the seventh embodiment can avoid interference between other articles R and the side gripping part 30 by changing the position of the side gripping part 30 in a plan view and switching the state of the side gripping part 30 without loading or unloading at the four corners. This can reduce the number of rotation operations by the turning mechanism, and can reduce heat generation from the device and wear on the parts of the turning mechanism.

[0070] The control method of the gripping device 1 in the eighth aspect is a control method of the gripping device 1 in any one of the first to seventh aspects, and includes a transport target data acquisition step (step S10) of acquiring transport target data indicating data regarding the item R to be transported by the gripping device 1, an image data acquisition step (step S14) of acquiring image data of the item R to be unloaded or a predetermined area including the area where the item R is to be loaded, a judgment step (step S16) of determining whether side gripping of the item R by the side gripping unit 30 is necessary for transporting the item R based on the transport target data, a switching step (step S18) of switching the side gripping unit 30 to the second state if it is determined in the judgment step that side gripping is not necessary, and a transport step (step S20) of supporting the item R with at least the upper gripping unit 20 and transporting it.

[0071] The control method of the gripping device 1 in the eighth aspect determines whether or not side gripping of the item R by the side gripping unit 30 is necessary based on data on the object to be transported, and if side gripping is necessary, positions the side gripping unit 30 in a first state, and if side gripping is not necessary, positions the side gripping unit 30 in a second state, etc., thereby optimizing the positioning of the side gripping unit 30, thereby improving the transport capacity.

[0072] In the control method for the gripping device 1 according to the ninth aspect, in the switching step (step S18), the presence or absence of an obstacle around the item R that may interfere with the side gripping portion 30 is determined based on the captured image data, and if an obstacle is present, the side gripping portion 30 is moved relative to the upper gripping portion 20 to a position where the side gripping portion 30 can avoid the obstacle.

[0073] The control method of the gripping device 1 according to the ninth aspect determines whether or not side gripping of the article R by the side gripping unit 30 is necessary based on the transport object data, and recognizes the surrounding situation of the article R to be transported based on the captured image data. This makes it possible to optimize the positioning of the side gripping unit 30, for example, by positioning the side gripping unit 30 in the first state when side gripping is necessary, and by positioning the side gripping unit 30 in the second state when side gripping is not necessary and there is a possibility of interference with an obstacle, thereby improving the transport capacity.

[0074] In the control method of the gripping device 1 according to the tenth aspect, the transport target data includes the number of items R, the position at which each item R is loaded or the position of each item R to be unloaded, and the order in which each item R is loaded or unloaded, and after the transport target data acquisition step (step S10), a captured image data acquisition step (step S14), a judgment step (step S16), a switching step (step S18), and a transport step (step S20) are repeatedly executed.

[0075] In the control method of the gripping device 1 according to the tenth aspect, the transport object data is included in upstream data from, for example, the management device 100 of the transport system in which the gripping device 1 is deployed. The transport order of multiple articles R is determined in advance by such transport object data, and the gripping device 1 is controlled based on this. In other words, the articles R are transported one after another in a predetermined order, and the positioning of the side gripping unit 30 can be optimized based on the transport object data and captured image data at that time, thereby improving the transport capacity.

[0076] Although the embodiments of the present disclosure have been described above, the embodiments are not limited to the contents of the description of these embodiments.

[0077] For example, in this embodiment, the side gripping part 30, the first arm part 40, and the second arm part 50 rotate around the rotation axis A of the flip-up mechanism 60 to move the side gripping part 30 between a position below and a position above the lower end of the upper gripping part 20, but this may be achieved by translational movement in the Z-axis direction. That is, the flip-up mechanism 60 may move the side gripping part 30 between a position below and a position above the lower end of the upper gripping part 20 by translating the side gripping part 30 in a direction perpendicular to the first suction surface 22a of the upper gripping part 20. In this case, the flip-up mechanism 60 is realized by a known mechanism such as a linear actuator including a motor, an air cylinder, or the like, a rack and pinion mechanism, a wire or link mechanism, or the like. [Explanation of symbols]

[0078] 1 Gripping device 10 base 10a Connecting part 12 Swivel shaft 14 Swivel mechanism 16 Lifting mechanism 20 Top grip part 20a First opposing surface 22 1st suction part 22a 1st suction surface 24 1st suction mechanism 30 Side grip part 30a 2nd facing surface 32 2nd suction part 32a 2nd suction surface 34 Second suction mechanism 40 1st arm 42 1st support part 44 1st telescopic mechanism 44a 1st fixed part 44b 1st moving part 50 2nd arm 52 Second support part 54 Second telescoping mechanism 54a 2nd fixed part 54b 2nd moving part 60 Flip-up mechanism 62 Fixed part 64 Rotating part 70 Imaging Device 80 I / O Devices 90 Control device 92 Communications Department 94 Memory section 96 Control Unit 100 Management device

Claims

1. An upper gripping portion having a first suction surface capable of being suctioned to an upper surface of an article; A side gripping portion having a second adsorption surface capable of adsorbing to a side surface of the article; a flip-up mechanism that can switch between a first state in which the side gripping portion is positioned below a lower end of the upper gripping portion and a second state in which the side gripping portion is positioned above the lower end of the upper gripping portion; A gripping device comprising:

2. a first suction mechanism that activates suction on the first suction surface when the first suction surface is in contact with an upper surface of the article; a second suction mechanism that activates suction on the second suction surface when the second suction surface is in contact with a side surface of the article; The gripping device of claim 1 .

3. The flip-up mechanism has a locking mechanism that positions the side grip portion in the second state. The gripping device according to claim 1 .

4. the flip-up mechanism rotates the side grip portion about a first rotation axis that is parallel to the first suction surface and the second suction surface and is positioned above the side grip portion in the first state; The gripping device according to claim 1 .

5. a first arm portion having one end connected to the side grip portion and being extendable and contractible in a first direction perpendicular to the second suction surface; a second arm having one end connected to the other end of the first arm and the other end connected to the upper gripping portion via the flip-up mechanism, the second arm being extendable and contractible in a second direction parallel to the second suction surface and perpendicular to the first rotation axis; The gripping device of claim 4 .

6. The flip-up mechanism translates the side gripping portion in a direction perpendicular to the first suction surface. The gripping device according to claim 1 .

7. A rotating mechanism is provided for rotating the upper gripping portion and the side gripping portion about a vertical second rotation axis. The gripping device according to claim 1 .

8. A method for controlling a gripping device according to any one of claims 1 to 7, comprising the steps of: a transport target data acquisition step of acquiring transport target data indicating data related to an item to be transported by the gripping device; an image data acquisition step of acquiring image data of an object to be unloaded or a predetermined area including an area in which the object is to be loaded; a determination step of determining whether or not side gripping of the article by the side gripping unit is required for the transport of the article based on the transport target data; a switching step of switching the side gripping portion to the second state when it is determined in the determining step that side gripping is not necessary; a conveying step of supporting and conveying the article by at least the upper gripping portion; A method for controlling a gripping device, comprising:

9. In the switching step, the presence or absence of an obstacle around the article that may interfere with the side gripping portion is determined based on the captured image data, and if the obstacle is present, the side gripping portion is moved relative to the upper gripping portion to a position where the side gripping portion can avoid the obstacle. A method for controlling a gripping device according to claim 8.

10. The transport target data includes a number of items, a location for loading or unloading each item, and an order for loading or unloading each item, After the transport target data acquisition step, the captured image data acquisition step, the determination step, the switching step, and the transport step are repeatedly executed. A method for controlling a gripping device according to claim 8.

Images