JP7686472B2 - Unloading device, unloading program, and unloading method - Google Patents

Description

Embodiments of the present invention relate to an unloading device, a program, and an unloading method.

For example, unloading devices are known that are used in logistics warehouses to unload cargo that is loaded on a loading section such as a pallet. Unloading devices are known to be configured to hold cargo in a holding section and unload the held cargo onto a destination such as a conveyor. This type of unloading device is known to be configured with a holding section that holds the cargo by adsorbing the top and sides of the cargo.

JP 2021-24679 A

The problem that this invention aims to solve is to provide an unloading device, an unloading program, and an unloading method that can improve the efficiency of unloading work.

The unloading device according to the embodiment includes a holding device, a sensor, a support unit, a first moving device, a second moving device, a rotation device, and a control device. The holding device includes an upper surface suction unit that suctions an upper surface of a load and a side surface suction unit that suctions a side surface of the load. The sensor detects whether the side surface suction unit interferes with the surroundings. The support unit supports the holding device rotatably around a single axis that intersects the vertical direction. The first moving device is connected to the support unit and moves the support unit. The second moving device is provided on the support unit and moves the side surface suction unit in a direction approaching the side surface of the load and in a direction away from the side surface. The rotation device maintains the support unit at a rotation position where the upper surface suction unit has moved downward from an initial position where the upper surface suction unit is approximately horizontal, around the single axis. The control device controls the holding device, the sensor, the first moving device, the second moving device, and the rotation device. The control device, when controlling the pivoting device to maintain the support portion at the initial position, controls the upper surface suction portion of the holding device to hold the luggage with the upper surface suction portion , and detects with the sensor whether or not moving the side suction portion toward the side of the luggage will cause interference with the surroundings when controlling the second moving device , and when it is determined based on the detection by the sensor that the side suction portion may interfere with the surroundings, controls the first moving device to lift the luggage to a predetermined height at which the side suction portion does not interfere with the surroundings , and when the luggage reaches the predetermined height at which the side suction portion does not interfere with the surroundings, controls the second moving device to move the side suction portion to the side and controls the holding device to adsorb the side of the luggage to the side suction portion, and then controls the pivoting device to tilt the support portion from the initial position to the pivoted position, and while maintaining the support portion in the pivoted position, controls the first moving device to move the luggage with the lower end of the luggage in contact with the loading surface of the luggage.

FIG. 1 is a perspective view showing a configuration of an unloading device according to an embodiment. FIG. 4 is a side view showing the holding device and the support part of the unloading device. FIG. 2 is a block diagram showing the configuration of the unloading device. 4 is a flowchart showing an example of the operation of the unloading device. 4 is a flowchart showing an example of the operation of the unloading device. FIG. 4 is a schematic diagram illustrating an example of the operation of the unloading device. FIG. 4 is a schematic diagram illustrating an example of the operation of the unloading device. FIG. 4 is a schematic diagram illustrating an example of the operation of the unloading device. FIG. 4 is a schematic diagram illustrating an example of the operation of the unloading device. FIG. 4 is a schematic diagram illustrating an example of the operation of the unloading device. FIG. 4 is a schematic diagram illustrating an example of the operation of the unloading device. FIG. 4 is a schematic diagram illustrating an example of the operation of the unloading device. FIG. 4 is a schematic diagram illustrating an example of the operation of the unloading device.

The unloading device 10 according to one embodiment will be described with reference to Figures 1 to 13.

Figure 1 is a perspective view showing the configuration of the unloading device 10. Figure 2 is a side view showing the holding device 70 and the support part 80 of the unloading device 10. Figure 3 is a block diagram showing the configuration of the unloading device 10. Figures 4 and 5 are flow charts showing an example of the operation of the unloading device 10. Figures 6 to 13 are schematic diagrams explaining an example of the operation of the unloading device 10.

As shown in Figures 1 to 3, the unloading device 10 includes, for example, a frame 20, an intermediate conveyor 30, a lifting device 40, a first sensor 50, a second sensor 60, a holding device 70, a support section 80, a first moving device 90, a second moving device 110, a rotating device 120, a third sensor 140, and a control device 130.

The unloading device 10 is used, for example, in a logistics warehouse, and holds luggage 2 from a luggage group 3 consisting of multiple luggage 2 loaded on a loading section 1 such as a pallet using a holding device 70, unloads the luggage 2 onto an intermediate conveyor 30, which is an example of a luggage destination, using a first moving device 90, and transports the luggage 2 to a main conveyor 4, which is an example of a transport destination, using the intermediate conveyor 30 and a lifting device 40.

The unloading device 10 is disposed, for example, between the placement section 1 and the main conveyor 4. In this embodiment, the direction of gravity is defined as the downward direction, and the vertical direction Z is defined as the forward direction, and the direction perpendicular to the vertical direction Z from the unloading device 10 to the placement section 1 is defined as the forward direction, and the direction perpendicular to both the vertical direction Z and the vertical direction X is defined as the width direction Y.

2, the luggage 2 is, for example, rectangular and has an upper surface 6, a side surface 7, and a lower surface 8. The side surface 7 includes a front surface 5a and a rear surface 5b. In the luggage group 3, the luggage 2 is arranged, for example, with the front surface 5a and the rear surface 5b perpendicular to the front-rear direction. Between two luggage 2 arranged in the vertical direction Z, an anti-slip agent 5 such as a glue is provided to prevent the luggage from collapsing. The anti-slip agent 5 is provided, for example, at least two places on the upper surface 6 of the luggage 2, spaced apart in the front-rear direction X. The two luggage 2 arranged in the vertical direction are fixed by the anti-slip agent 5. As shown in FIG. 1, the main conveyor 4 is configured to be able to transport the luggage 2 unloaded by the unloading device 10 to a secondary destination of the unloading device 10.

The frame 20 supports the intermediate conveyor 30, the lifting device 40, the first sensor 50, the second sensor 60, the holding device 70, the support section 80, the first moving device 90, the second moving device 110, and the rotating device 120.

The frame 20 includes, for example, a frame main body 21 and a ridge portion 22 .
The frame body 21 supports the intermediate conveyor 30, the lifting device 40, the second sensor 60, the holding device 70, the support section 80, the first moving device 90, the second moving device 110, and the rotating device 120. The frame body 21 has a first opening 23 facing the placement section 1 and a second opening 24 facing the main conveyor 4. The first opening 23 and the second opening 24 are configured to allow the baggage 2 to pass through in the front-rear direction X.

The frame main body 21 includes, for example, a plurality of (eg, four) pillar portions 25 and a plurality of beam portions 26 .
The multiple pillar portions 25, for example, form a first opening 23 by two pillar portions 25 adjacent to each other in the width direction Y and two beam portions 26 provided at the upper and lower ends, and a second opening 24 by two pillar portions 25 adjacent to each other in the width direction Y behind the two pillar portions 25 that form the first opening 23 and two beam portions 26 provided at the upper and lower ends.

The rib portion 22 is provided at the front end of the upper end of the frame body 21. The rib portion 22 protrudes forward from the frame body 21. The rib portion 22 is disposed, for example, in a position aligned with the placement portion 1 in the vertical direction.

The intermediate conveyor 30 is housed within the frame body 21. The intermediate conveyor 30 is configured to be able to transport luggage 2 that has been transported into the frame body 21 from the first opening 23 to the main conveyor 4 through the second opening 24.

The intermediate conveyor 30 is, for example, a belt conveyor. The intermediate conveyor 30 includes, for example, a belt 31, a first drive unit 32, and a first transmission mechanism 33. The intermediate conveyor 30 may be a roller conveyor.

The belt 31 is, for example, an endless belt. The front end of the belt 31 is disposed near the first opening 23. The rear end of the belt 31 is disposed near the second opening 24. The gap between the rear end of the belt 31 and the main conveyor 4 is set to a gap that prevents the baggage 2 transported by the intermediate conveyor 30 from falling downward from between the belt 31 and the main conveyor 4.

The first driving unit 32 generates a driving force for driving the belt 31. The first driving unit 32 is, for example, a motor.
The first transmission mechanism 33 rotates the belt 31 by receiving the driving force generated by the first driving unit 32. The first transmission mechanism 33 rotatably supports the belt 31 in an orientation in which an upper surface 34 of the belt 31 is, for example, a plane perpendicular to the vertical direction Z. The first transmission mechanism 33 includes, for example, a pair of pulleys provided at the front end and the rear end of the belt 31, respectively, for rotatably supporting the belt 31, and a shaft portion connecting the pulley at the rear end and the main shaft of the first driving unit 32 to rotate the pulley at the rear end integrally with the first driving unit 32.

When the intermediate conveyor 30 is configured in this manner, the belt 31 is rotated by driving the first drive unit 32, and the luggage 2 placed on the belt 31 is transported to the main conveyor 4.

The lifting device 40 is configured to be able to raise and lower the intermediate conveyor 30 within the frame body 21. The lifting device 40 is provided, for example, in the frame body 21. The lifting device 40 includes, for example, a second drive unit 41 and a second transmission mechanism 42.

The second drive unit 41 generates a driving force that raises and lowers the intermediate conveyor 30. The second drive unit 41 is, for example, a motor. The second drive unit 41 is installed, for example, at the upper end of the frame body 21.

The second transmission mechanism 42 transmits the driving force generated by the second drive unit 41 to the intermediate conveyor 30 to raise and lower the intermediate conveyor 30. The second transmission mechanism 42 includes, for example, a shaft 43 and a plurality of wires 44.

The shaft 43 is rotated by the second drive unit 41. The shaft 43 is fixed, for example, directly or indirectly to the main shaft of the second drive unit 41. The shaft 43 is installed at the upper end of the frame body 21 in a position parallel to the horizontal direction, for example, parallel to the width direction Y.

One end of each of the multiple wires 44 is fixed to the shaft 43, and the other end of each is fixed to the intermediate conveyor 30.

The lifting device 40 configured in this manner raises and lowers the intermediate conveyor 30 by driving the second drive unit 41 to rotate the shaft 43 and wind or unwind the multiple wires 44 onto or from the shaft 43.

The first sensor 50 detects information about the luggage 2 in the luggage group 3, including position information about the luggage 2. The first sensor 50 transmits the detection result to the control device 130. The first sensor 50 is, for example, a stereo camera. The first sensor 50 measures the distance between the first sensor 50 and the luggage 2 based on the parallax when images are captured from two different points. In addition to the position information about the luggage 2, the first sensor 50 detects the size and shape of the luggage 2 as an example of information about the luggage 2. The first sensor 50 is installed, for example, on the frame 20, specifically, on the eaves 22. The first sensor 50 is disposed in a position aligned with the placement unit 1 in the vertical direction. The second sensor 60 measures the height of the bottom surface 8 of the luggage 2 on the movement trajectory of the luggage 2 held by the holding device 70 and moved to the intermediate conveyor 30. The second sensor 60 transmits the detection result to the control device 130. The second sensor 60 is installed, for example, between the placement unit 1 and the intermediate conveyor 30, below the intermediate conveyor 30. The second sensor 60 is installed, for example, at the front end of the lower end of the frame body 21 .

The second sensor 60 is, for example, a laser range finder (LRF). The second sensor 60 irradiates, for example, an upward laser beam such as infrared laser beam, visible light beam, ultraviolet light beam, or X-ray beam onto the underside 8 of the luggage 2 being moved between the placement unit 1 and the intermediate conveyor 30, and receives the laser beam reflected by the underside 8. Then, the second sensor 60 detects the height of the underside 8 of the luggage 2 based on the time between irradiation and reception of the reflected beam.

The holding device 70 includes an upper surface suction portion 71 and a side surface suction portion 72. The holding device 70 holds the luggage 2 by suctioning the upper surface 6 of the luggage 2 with the upper surface suction portion 71 and by suctioning the side surface 7 of the luggage 2 with the side surface suction portion 72. The holding device 70 releases the hold of the luggage 2 by releasing the suction by the upper surface suction portion 71 and the side surface suction portion 72.

As shown in FIG. 3, in this embodiment, the holding device 70 is equipped with a negative pressure generating device 77 including a pump, and by driving this negative pressure generating device 77, the upper surface suction portion 71 and the side surface suction portion 72 suction the luggage 2.

As shown in FIG. 2 , the upper surface suction portion 71 includes, for example, a first main body 73 and one or a plurality of first suction pads 74 .
The first body 73 is connected to the negative pressure generating device 77. The first body 73 is supported by a support portion 80. The first body 73 has, for example, a lower surface 73a formed in a plane perpendicular to the up-down direction Z. The first body 73 is formed in, for example, a rectangular parallelepiped shape.

The first suction pads 74 are provided, for example, in a plurality on the first main body 73. The plurality of first suction pads 74 are provided, for example, on the lower surface 73a. The plurality of first suction pads 74 are formed in a cylindrical shape, for example, a cylindrical shape having a truncated cone shape, with the lower end being an open end 74a. The plurality of first suction pads 74 are connected to the negative pressure generating device 77 via the first main body 73. The plurality of open ends 74a of the plurality of first suction pads 74 are arranged, for example, in the same plane perpendicular to the up-down direction.

The side suction portion 72 includes, for example, a second main body 75 and one or more second suction pads 76 .
The second body 75 is connected to the negative pressure generator 77. The second body 75 is supported by a support portion 80. The second body 75 has, for example, a front surface 75a formed in a plane perpendicular to the front-rear direction X. The second body 75 is formed, for example, in a rectangular parallelepiped shape.

The second suction pads 76 are provided, for example, in multiple numbers, on the front surface 75a of the second main body 75. The second suction pads 76 are formed in a cylindrical shape, for example, a truncated cone shape, with the front end being the open end 76a. The multiple second suction pads 76 are connected to the negative pressure generating device 77 via the second main body 75. The multiple open ends 76a of the multiple second suction pads 76 are arranged, for example, on the same plane perpendicular to the front-rear direction X.

The negative pressure generating device 77 is configured to generate negative pressure in the first suction pads 74 and the second suction pads 76, and to be able to release this negative pressure. The negative pressure generating device 77 includes, for example, a pump, a first tube connecting the pump and the upper surface suction part 71, a second tube connecting the pump and the side surface suction part 72, and valves provided on each of the first tube and the second tube and connecting the first tube and the second tube to the atmosphere. The pump may be shared by the upper surface suction part 71 and the side surface suction part 72, or one pump may be provided for each of the upper surface suction part 71 and the side surface suction part 72.

In the holding device 70 configured in this manner, the upper suction portion 71 and the side suction portion 72 hold the luggage 2 by vacuum suction due to the negative pressure generated by the negative pressure generating device 77. When the valve is opened to release the negative pressure in the first suction pad 74 and the second suction pad 76, in other words, when a vacuum break occurs, the upper suction portion 71 and the side suction portion 72 release the luggage 2.

The support unit 80 supports the holding device 70 on the first moving device 90 in a position in which the upper surface suction unit 71 can suction the upper surface 6 of the luggage 2 and the side surface suction unit 72 can suction the rear surface 5b of the luggage 2.

The support unit 80 also supports the holding device 70 on the first moving device 90 so that it can rotate about an axis perpendicular to the up-down direction Z. In this embodiment, the support unit 80 supports the holding device 70 so that it can rotate between the initial position A1 and the rotation position A2 about an axis parallel to the width direction Y.

The initial position A1 is a position where the upper surface suction part 71 can suction the upper surface of the luggage 2 placed on the loading part 1, and the side surface suction part 72 can suction the rear surface 5b of the luggage 2. The initial position A1 is a position where the surface of the upper surface suction part 71 that abuts against the upper surface 6 is approximately horizontal.

Here, "substantially horizontal" includes horizontal and having a slight inclination with respect to the horizontal. For example, depending on the assembly accuracy of each component of the support part 80 and the holding device 70 of the unloading device 1, when an attempt is made to make the surface of the upper surface suction part 71 that abuts against the upper surface 6 horizontal, the surface may be slightly inclined. "Having a slight inclination with respect to the horizontal" includes an error in which the surface of the upper surface suction part 71 that abuts against the upper surface 6 is slightly inclined with respect to the horizontal when the rotating device 120 described later is controlled so that the surface of the upper surface suction part 71 that abuts against the upper surface 6 is horizontal. In this embodiment, the initial position A1 is, for example, a position where the opening ends 74a of the multiple first suction pads 74 of the upper surface suction part 71 are horizontal and the opening ends 76a of the multiple second suction pads 76 are perpendicular to the front-rear direction X.
The rotation position A2 is a position where the side surface adsorption portion 72 is disposed above the initial position A1.

The support portion 80 includes, for example, a support portion main body 81 and a connecting portion 82 .
The support body 81 is provided with an upper surface suction portion 71 and a side surface suction portion 72. The support body 81 includes, for example, a first portion 83 and a second portion 84.

The first portion 83 is provided with an upper surface suction portion 71. The first portion 83 is formed in a shape that is long in the front-rear direction X. The upper surface suction portion 71 is provided, for example, at the front end of the first portion 83.

The second part 84 is provided with a side suction part 72, for example, via a second moving device 110. The second part 84 is provided, for example, at the rear end of the first part 83, and is formed into a long shape extending downward.

The connecting part 82 connects the support body 81 to the first moving device 90 so as to be rotatable about an axis parallel to the width direction Y. The connecting part 82 includes, for example, a bracket 85 and a rotation shaft 86.

The bracket 85 is fixed to, for example, the first moving device 90. The pivot shaft 86 pivotally connects, for example, the rear end of the first portion 83 to the bracket 85. The pivot shaft 86 is formed parallel to the width direction Y.

As shown in FIG. 1, the first moving device 90 is connected to the support section 80 and moves the support section 80. The first moving device 90 then moves the holding device 70 between the placement section 1 and the intermediate conveyor 30 via the support section 80. In other words, the first moving device 90 moves the support section 80 between the holding position where the luggage 2 is held and the destination where the luggage 2 is unloaded.

The first moving device 90 is supported, for example, by the frame body 21. The first moving device 90 includes, for example, a horizontal moving device 91 and a lifting device 92.

The horizontal movement device 91 moves the support part 80 in the horizontal direction. The horizontal movement device 91 includes, for example, a base part 93, a movable part 95, and an arm 94.

The base 93 is formed above the intermediate conveyor 30 inside the frame body 21 and is movable in the vertical direction Z. The base 93 is formed, for example, in a flat plate shape.

The movable part 95 is provided on the base 93. The movable part 95 moves the arm 94 in the front-rear direction X and the width direction Y relative to the base 93. As shown in FIG. 3, the movable part 95 includes, for example, a front-rear direction actuator 95a and a width direction actuator 95b. The front-rear direction actuator 95a moves the arm 94 in the front-rear direction X. The width direction actuator 95b moves the arm 94 in the width direction Y.

The arm 94 is formed in a shape that extends in the front-rear direction X. The arm 94 is supported by a movable part 95. The bracket 85 is fixed to the front end of the arm 94.

The lifting device 92 moves the horizontal movement device 91 in the vertical direction Z. The lifting device 92 includes, for example, a shaft 96, a vertical actuator 97, and a number of wires 98.

The shaft 96 is rotatably supported at the upper end of the frame body 21 in a position parallel to the width direction Y, for example.
The vertical actuator 97 is fixed to, for example, the upper end of the frame body 21 and rotates the shaft 96 .
A plurality of wires 98 have one end fixed to the shaft 96 and the other end fixed to the base 93 of the horizontal movement device 91 .

As shown in FIG. 2, the second moving device 110 is provided on the support portion 80 and moves the side suction portion 72 toward and away from the side of the luggage 2, which in this embodiment is the rear surface 5b. The second moving device 110 moves the side suction portion 72 in the front-rear direction X. The second moving device 110 includes, for example, a base portion 111, a moving portion 112, and a third driving portion 113.

The base 111 is fixed to, for example, the second portion 84 of the support body 81 .
The moving portion 112 is supported by the base portion 111 so as to be movable in the front-rear direction X, for example.
The third driving unit 113 is fixed to, for example, the base unit 111. The third driving unit 113 moves the moving unit 112 in the front-rear direction X.

The rotation device 120 rotates the support section 80 between the initial position A1 and the rotation position A2. The rotation device 120 also maintains the support section 80 at the initial position A1 while the holding device 70 is holding the luggage 2. The rotation device 120 also maintains the support section 80 at the rotation position A2 while the holding device 70 is holding the luggage 2. The rotation device 120 may be configured to be able to maintain the support section 80 at any position between the initial position A1 and the rotation position A1 while the holding device 70 is holding the luggage 2, for example.

The rotation device 120 includes, for example, an arm 121 and a rotation actuator 122.

The arm 121 is provided, for example, on the arm 94 of the horizontal movement device 91, and is formed above the arm 94 in a shape that extends in the front-rear direction X. The front end of the arm 121 is disposed in a position that faces the front end of the first part 83 of the support body 81 in the up-down direction.

The rotation actuator 122 connects the front end of the arm 121 and the front end of the first part 83, and rotates the support part 80 around the rotation axis 86 by expanding and contracting in the vertical direction. The rotation actuator 122 is, for example, an air cylinder.

2 and 3, the rotation actuator 122 includes, for example, a cylinder 123, a piston 124, a pump 125, and a circuit 126. In the rotation actuator 122, the pump 125 and the cylinder 123 are connected by the circuit 126, and the piston 124 moves in the vertical direction Z relative to the cylinder 123 by air supplied to the pump 125.

The pump 125 supplies air to the cylinder 123 via a circuit 126 .
The circuit 126 connects the pump 125 and the cylinder 123. For example, the circuit 126 includes a flow path and one or more relief valves. The circuit 126 supplies, to the cylinder 123, a pressure for maintaining the cylinder 123 in the initial position A1 or a pressure for maintaining the cylinder 123 in the rotation position A2 by controlling the relief valve.

This type of rotation device 120 adjusts the amount of protrusion of the piston 124 relative to the cylinder 123, thereby controlling the amount of rotation of the support part 80 around the rotation axis 86.

In the above-mentioned rotating actuator 122, the circuit 126 is controlled to switch the pressure supplied to the cylinder 123 between the pressure for maintaining the initial position A1 and the pressure for maintaining the rotation position A2. However, this is not limiting. In another example, the rotating actuator 122 may not include the circuit 126, and the pump 125 may be configured to supply the pressure for maintaining the initial position A1 and the pressure for maintaining the rotation position A2 to the cylinder 123. Alternatively, the pump 125 and the circuit 126 may form a hydraulic circuit. Alternatively, the rotating device 120 may include a motor as the rotating actuator 122, and the driving force generated by the motor may be used to maintain the support unit 80 in the initial position A1 when the holding device 70 holds the luggage 2, or to maintain the support unit 80 in the rotation position A2 when the holding device 70 holds the luggage 2.

The third sensor 140 detects information to determine whether there is space behind the luggage 2 in which the side suction part 72 can be moved to the rear surface 5b of the luggage 2 when the top surface suction part 71 is suctioned to the top surface 6 of the luggage 2 to be held in the holding position.

In this embodiment, when the upper surface suction portion 71 suctions the upper surface 6, the multiple first suction pads 74 shrink in the vertical direction Z due to negative pressure. When the opening ends 74a of the multiple first suction pads 74 are in contact with the upper surface 6 of the luggage 2 but the multiple first suction pads 74 have not yet suctioned the upper surface 6, the multiple first suction pads 74 do not shrink in their axial direction.

For this reason, as shown in FIG. 11, for example, in the holding position, when the opening ends 74a of the first suction pads 74 are in contact with the upper surface 6 of the luggage 2 but the first suction pads 74 are not adsorbing the upper surface 6, the first suction pads 74 are in a state before they shrink, so it may be possible to position the side suction portion 72 behind the luggage 2. However, in this state, if the negative pressure generator 77 creates negative pressure within the first suction pads 74, causing the first suction pads 74 to shrink in the axial direction, there is a risk that the side suction portion 72 will interfere with the luggage 2 or the placement portion 1 below.

The third sensor 140 thus detects the distance to the luggage 2 or the placement section 1 below the side suction section 72 when the opening ends 74a of the multiple first suction pads 74 are in contact with the upper surface 6 of the luggage 2 but the multiple first suction pads 74 are not suctioning the upper surface 6. In this embodiment, the third sensor 140 detects the distance to the luggage 2 or the placement section 1 diagonally downward and forward. The third sensor 140 transmits the detection result to the control device 130. The third sensor 140 is installed, for example, at the lower end of the side suction section 72, specifically, at the lower end of the second main body 75. The third sensor 140 is, for example, a laser range finder. The third sensor 140 irradiates a laser diagonally downward and forward.

The control device 130 controls the operation of each part of the unloading device 10. The control device 130 may also control the main conveyor 4. The main conveyor 4 may be controlled by another control device. The control device 130 is provided, for example, on the frame 20.

The control device 130 controls the holding device 70, the first moving device 90, the second moving device 110, and the rotating device 120. The control device 130 detects the position, shape, and size of the luggage 2 on the placement section 1 based on the detection result of the first sensor 50. The control device 130 detects the height of the bottom surface of the luggage 2 being unloaded from the placement section 1 to the intermediate conveyor 30 based on the detection result of the second sensor 60. The control device 130 determines, based on the detection result of the third sensor 140, whether or not there is space to place the side suction section 72 behind the luggage 2 when the top surface 6 of the luggage 2 is suctioned by the top surface suction section 71 at the holding position.

The control device 130 also controls the rotation device 120 to maintain the support unit 80 at the initial position A1, controls the holding device 70 to hold the luggage 2, controls the first moving device 90 to raise the luggage 2 to a predetermined height, and then controls the rotation device 120 to maintain the support unit 80 at the rotation position A2, and controls the first moving device 90 to move the luggage 2 with the lower end of the luggage 2 in contact with the placement surface of the luggage 2.

The control device 130 constitutes a computer for controlling the unloading device 10. The control device 130 has, for example, a communication interface 131, a processor 132, a memory 133, and a storage 134. These communicate with each other via a bus line 135.

The communication interface 131 is an interface used for communication with external devices. The communication interface 131 has terminals and circuits that correspond to communication standards and the like that allow the control device 130 to communicate with each part of the unloading device 10.

The communication interface 131 is connected to and communicates with the intermediate conveyor 30, the first sensor 50, the second sensor 60, the holding device 70, the first moving device 90, the second moving device 110, the rotating device 120, and the third sensor 140 by wire or wirelessly. The control device 130 controls the intermediate conveyor 30, the first sensor 50, the second sensor 60, the holding device 70, the first moving device 90, the second moving device 110, the rotating device 120, and the third sensor 140.
The processor 132 is configured by, for example, a CPU (Central Processing Unit). The memory 133 includes a ROM (Read Only Memory) which is a read-only data memory or a RAM (Random Access Memory) which temporarily stores data. The storage 134 may be a large-capacity storage such as a HDD (Hard Disk Drive) or an SSD (Solid State Drive). The memory 133 or the storage 134 stores control programs and various data of each device of the unloading device 10. The control program includes a program related to unloading of the baggage 2 placed on the loading section 1. The processor 132 performs various processes based on the programs stored in the memory 133 or the storage 134. That is, the processor 132 executes various programs as a software function unit. Instead of the CPU, an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array) as a hardware function unit may be used.

Next, an example of the operation of the unloading device 10 will be described with reference to Figs. 4 to 11. The control device 130 of the unloading device 10 unloads the luggage 2 placed on the loading section 1 by the processor 132 executing a program related to unloading the luggage 2 stored in the memory 133.

As shown in FIG. 4, the control device 130 sets the tilt amount of the support part 80 to "small" (step ST1). Here, setting the tilt amount to "small" means controlling the pump 125 and the circuit 126 to control the amount of protrusion of the piston 124 relative to the cylinder 123, thereby maintaining the support part 80 at the initial position A1.

Next, the control device 130 detects the position of the luggage 2 to be unloaded based on the detection result of the first sensor 50, and controls the first moving device 90 to move the upper surface suction unit 71 to the luggage 2 to be unloaded (step ST2). Here, moving the upper surface suction unit 71 to the luggage 2 means moving the upper surface suction unit 71 to a position where it will suction the upper surface 6 of the luggage 2.

Next, the control device 130 controls the holding device 70 to perform top surface gripping by adsorbing the top surface 6 with the top surface adsorption section 71 (step ST3).

Next, based on the detection result of the third sensor 140, the control device 130 determines whether or not it has detected other luggage 2 or loading section 1 that would prevent the side suction section 72 from suctioning the rear surface 5b while the top surface 6 is being suctioned by the top surface suction section 71 (step ST4).

Specifically, when the control device 130 determines based on the detection result of the third sensor 140 that the distance from the side suction portion 72 to another piece of luggage 2 or the loading portion 1 while the upper surface suction portion 71 is suctioning the upper surface 6 is not a distance that prevents the side suction portion 72 from suctioning the rear surface 5b of the piece of luggage 2 (NO in step ST4), it controls the second moving device 110 to move the side suction portion 72 to the piece of luggage 2 as shown in FIG. 6 (step ST5). Here, moving the side suction portion 72 to the piece of luggage 2 means that the opening end 76a of the second suction pad 76 of the side suction portion 72 abuts against the rear surface 5b of the piece of luggage 2 and moves it to a position where the side suction portion 72 can suction the piece of luggage 2.

Next, as shown in FIG. 6, the control device 130 controls the holding device 70 to perform side gripping by adsorbing the rear surface of the luggage 2 with the side suction portion 72 (step ST6).

Next, the control device 130 sets a timer (step ST7). Here, setting the timer means starting to measure the time that is estimated to be required for the luggage 2 to move from the holding position to the lifting target position at a predetermined height.

The target lifting position is the position where the front end of the luggage 2 comes into contact with the placement surface of the luggage 2 when the support part 80 is rotated to the rotation position A2. When the support part 80 is in the rotation position A2, the front end of the luggage 2 becomes the lower end of the luggage 2. In this embodiment, the placement surface is the upper surface of the luggage 2 below, or the upper surface of the placement part 1. The target lifting position is a height position where the side suction part 72 does not interfere with other luggage 2 below the side suction part 72, or with the placement part 1.

The lifting target position is set, for example, according to the length of the luggage 2 in the forward and backward directions. The control device 130 detects the length of the luggage 2 in the forward and backward directions based on the detection result of the first sensor 50, and sets the lifting target position based on the length of the luggage 2 in the forward and backward directions and the rotation angle from the initial position A1 to the rotation position A2.

The lifting target position may also be set based on the length of the luggage 2 in the forward/rearward direction X that is input in advance to the memory 133. Alternatively, the lifting target position may be a predetermined height that is set in advance.

Next, the control device 130 controls the first moving device 90 to start lifting the luggage 2 from the holding position (step ST8). As shown in FIG. 7, the control device 130 moves the first moving device 90 toward the luggage 2 relative to the side suction portion 72 while moving the luggage 2 upward. In other words, the control device 130 lifts the luggage 2 by moving the luggage 2 forward while moving it upward.

In this way, by moving the support part 80 upward and forward while being maintained in the initial position A1, a force in the peeling direction as well as a force in the shearing direction acts on the anti-slip agent 5 that secures the luggage 2 held by the holding device 70 and the luggage 2 below. These forces cause the anti-slip agent 5 provided between the luggage 2 held by the holding device 70 and the luggage 2 below to peel off from the luggage 2, and the two luggage 2 above and below are released from their fastening.

Next, as shown in FIG. 8, when the luggage 2 reaches the lifting target position (step ST9), the control device 130 controls the first moving device 90 to stop lifting the luggage 2 (step ST10). The control device 130 also stops driving the first moving device 90 and maintains the luggage 2 at the lifting target position until the timer set in step ST7 fires (step ST11). The timer firing indicates that the time assumed to be required to lift the luggage 2 to the lifting target position has elapsed.

When the timer fires, the control device 130 sets the tilt amount of the support part 80 to "large" as shown in Figures 5 and 9 (step ST12). Here, setting the tilt amount to "large" means controlling the pump 125 and the circuit 126 to control the amount of protrusion of the piston 124 relative to the cylinder 123, thereby maintaining the support part 80 at the rotation position A2. By rotating the support part 80 to the rotation position A2, the front end of the luggage 2 held by the holding device 70 comes into contact with the upper surface of the luggage 2 below, or the upper surface of the placement part 1, which is the placement surface of the luggage 2.

When the control device 130 sets the tilt amount of the support unit 80 to "large", it then controls the first moving device 90 and the lifting device 40 to start drawing in the luggage 2, as shown in FIG. 10 (step ST13). Here, drawing in the luggage 2 means detecting the height position of the lower end of the luggage 2 held by the holding device 70 based on the detection result of the second sensor 60, controlling the lifting device 40 to adjust the position of the upper surface of the intermediate conveyor 30 to the height position of the lower end of the luggage 2 held by the holding device 70, and controlling the first moving device 90 to draw the luggage 2 into the frame main body 21 through the first opening 23 of the frame main body 21 and place it on the intermediate conveyor 30. Here, by maintaining the support unit 80 at the rotation position A2, the luggage 2 is moved with its front end in contact with the upper surface 6 of the luggage 2 below or the upper surface of the placement unit 1.

Next, when the luggage 2 reaches the retraction target position (step ST14), the control device 130 controls the holding device 70 to release the luggage 2 (step ST15). The luggage 2 reaching the retraction target position means that the luggage 2 reaches a position on the intermediate conveyor 30 where it will not fall from the intermediate conveyor 30. Releasing the luggage 2 means controlling the pump 125 and the circuit 126 to cause a vacuum break in the multiple first suction pads 74 and the multiple second suction pads 76, releasing the suction of the upper surface 6 by the multiple first suction pads 74, and releasing the suction of the rear surface 5b by the multiple second suction pads 76.

Next, when the control device 130 releases the luggage 2, it sets the tilt amount of the support part 80 to "small" (step ST16).

In this way, unloading of one piece of luggage 2 is completed.

In addition, when the control device 130 detects the luggage 2 based on the detection result of the third sensor 140 in step ST4, that is, when it detects that the side suction unit 72 is at risk of interfering with the surrounding luggage 2 or the placement unit 1 below (YES in step ST4), it lifts the luggage 2 and raises it to the target position before the luggage 2 is attracted by the side suction unit 72, and then the luggage 2 is attracted by the side suction unit 72. For example, similar to steps ST8 to ST11, the control device 130 lifts the luggage 2, the upper surface 6 of which is attracted by the upper surface suction unit 71, and raises it to the target position, and then, similar to steps ST5 to ST6, attracts the luggage 2 by the side suction unit 72. Specifically, the control device 130 performs control of steps ST17 to ST23.

Step ST17 corresponds to step ST7. Step ST18 corresponds to step ST8. Step ST19 corresponds to step ST9. Step ST20 corresponds to step ST10. Step ST21 corresponds to step ST11. Step ST22 corresponds to step ST5. Step ST23 corresponds to step ST6.

As shown in FIG. 11, when the control device 130 detects luggage 2 based on the detection result of the third sensor 140 (YES in step ST4), it sets a timer (step ST17).

Next, as shown in FIG. 12, the control device 130 controls the first moving device 90 to start lifting the support unit 80 and the luggage 2 (step ST18), and when the support unit 80 and the luggage 2 rise to the lifting target position (step ST19), the control device 130 controls the first moving device 90 to stop lifting the luggage 2 (step ST20).
After the control device 130 stops driving the first moving device 90, when the timer fires (step ST21), it controls the second moving device 110 to move the side suction portion 72 to the rear surface 5b of the luggage 2, as shown in Figure 13 (step ST22).

Next, the control device 130 controls the holding device 70 to adsorb the rear surface 5b of the luggage 2 using the side suction portion 72 (step ST23).

When the side suction unit 72 has adsorbed the rear surface 5b, the control device 130 proceeds to step ST12. In this way, if the side suction unit 72 cannot adsorb the luggage 2 placed on the loading unit 1, the top surface 6 is adsorbed by the top surface suction unit 71, and then the luggage 2 is raised to a position where the side suction unit 72 does not interfere with the luggage 2 or loading unit 1 below, and then the luggage 2 is adsorbed by the side suction unit 72.

In the unloading device 10 configured in this manner, when the luggage 2 is held by the holding device 70 at the holding position, the support part 80 is maintained at the initial position A1 by the rotating device 120, and the luggage 2 is lifted and raised to the target position.

As a result, when the luggage 2 is raised, the position of the holding device 70 around the rotation axis 86 does not change, so even if the luggage 2 is fixed to the luggage 2 below by the anti-slip agent 5, the fixation of the two luggage 2 arranged vertically by the anti-slip agent 5 can be efficiently released by the action of lifting the luggage 2.

That is, when lifting the luggage 2, the anti-slip agent 5 acts as a resistance, but by maintaining the support part 80 in the initial position A1, the force that tries to release the fixation by the anti-slip agent 5 is prevented from escaping, so that the action of lifting the luggage 2 can efficiently release the fixation by the anti-slip agent 5.

Furthermore, when the luggage 2 is lifted up to the target position, the support unit 80 is rotated to rotation position A2 by the rotation device 120. As a result, the luggage 2 held by the holding device 70 tilts, and one end of the underside of the luggage 2 that is rearward in the retraction direction abuts against the luggage 2 or the placement unit 1 below. In this way, the posture of the luggage 2 is stabilized by the luggage 2 or placement unit 1 below being supported during movement. As a result, the speed at which the luggage 2 is retracted by the first moving device 90 can be increased.

In this way, the luggage 2 can be efficiently released from its position secured by the anti-slip agent 5, and the speed at which the luggage 2 is pulled in can be increased, improving the efficiency of the unloading operation.

Furthermore, when lifting the luggage 2 to the target lifting position, the luggage 2 is moved toward the luggage 2 side of the side suction portion 72 while being lifted. In other words, the luggage 2 is lifted along a direction that is inclined with respect to the up-down direction. As a result, a force in the shear direction is applied to the anti-slip agent 5 in addition to a force in the peeling direction, so that the fixation of the luggage 2 by the anti-slip agent 5 can be efficiently released.

Furthermore, by moving the luggage 2 upward while moving in a direction from the side suction portion 72 toward the luggage 2, it becomes possible to press the luggage 2 with the side suction portion 72. By pressing the luggage 2 with the side suction portion 72, it is possible to prevent the side suction portion 72 from peeling off from the luggage 2 when the luggage 2 is raised.

Furthermore, if there is a risk that the side suction parts 72 may interfere with the luggage 2 or the placement part 1 below when the luggage 2 is suctioned by the upper suction parts 71, the luggage 2 is suctioned and held by the upper suction parts 71, the luggage 2 is lifted and raised to the target position, and then the rear surface of the luggage 2 is suctioned by the side suction parts 72. In this way, even if there is a risk of interference between the side suction parts 72 and the luggage 2 below, the luggage 2 can be held by the side suction parts 72, making it possible to stably hold the luggage 2. Also, by lifting the luggage 2 to the target lifting position and then suctioning the luggage 2 by the side suction parts 72, it becomes possible to use the side suction parts 72.

Thus, according to this embodiment, the holding device 70 holding the luggage 2 in the holding position is raised to the lifting target position while being maintained in the initial position A1, and then the holding device 70 is rotated to the rotation position A2 and maintained in that position. This allows the fastening of the two upper and lower luggage pieces 2 by the anti-slip agent 5 to be released efficiently, and furthermore, when the luggage 2 is pulled in, the rear end of the luggage 2 in the pulling direction of its underside abuts against the luggage 2 below or the placement section 1, stabilizing the luggage 2, and the speed at which the luggage 2 is pulled in can be increased. This improves the efficiency of the unloading operation.

The unloading device 10 is not limited to the above example. For example, in the above example, the rotation device 120 is configured to rotate the support unit 80 to the initial position A1 and the rotation position A2 by the rotation actuator 122 and maintain the support unit 80 at the initial position A1 or the rotation position A2, but is not limited to this. In another example, the rotation device 120 may be configured to include multiple springs and to rotate the support unit 80 to the initial position A1 or the rotation position A2 by switching between the multiple springs and maintain the support unit 80 at the initial position A1 or the rotation position A2.

In the above example, the rotation device 120 has been described as being configured to rotate the support unit 80 between the initial position A1 and the rotation position A2 and maintain the support unit 80 at each position, but is not limited to this. In other examples, the rotation device 120 may be configured to be able to maintain the support unit 80 at any position between the initial position A1 and the rotation position A2.

According to at least one embodiment described above, the holding device 70 holding the luggage 2 in the holding position is raised to the lifting target position while being maintained in the initial position A1, and then the holding device 70 is rotated to the rotation position A2 and maintained in that position. This allows the fastening of the two upper and lower luggage 2 by the anti-slip agent 5 to be efficiently released, and furthermore, when the luggage 2 is pulled in, the rear end of the luggage 2 in the pulling direction of the underside of the luggage 2 abuts against the lower luggage 2 or the placement section 1, stabilizing the luggage 2, and the speed at which the luggage 2 is pulled in can be increased. This improves the efficiency of the unloading operation.

Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims.
The following is a summary of the claims of this application as filed.
[Appendix 1]
A holding device including an upper surface suction portion that suctions an upper surface of the luggage and a side surface suction portion that suctions a side surface of the luggage;
a support portion that supports the holding device so as to be rotatable about a single axis that intersects with the vertical direction;
A first moving device connected to the support and configured to move the support;
a rotation device that maintains the support portion at a rotation position around the single axis where the upper surface suction portion has moved downward from an initial position where the upper surface suction portion is substantially horizontal to a rotation position where the upper surface suction portion has moved downward from the initial position;
a control device which controls the holding device to hold the luggage while controlling the rotating device to maintain the support part at the initial position, controls the first moving device to raise the luggage to a predetermined height, and then controls the first moving device to move the luggage with a lower end of the luggage in contact with a placement surface for the luggage while controlling the rotating device to maintain the support part at the rotated position;
An unloading device comprising:
[Appendix 2]
The unloading device of claim 1, wherein the control device controls the first moving device to lift the support portion and the luggage along a direction intersecting the vertical direction.
[Appendix 3]
The unloading device according to claim 2, wherein the intersecting direction is a direction from the side suction portion toward the luggage side as it moves upward.
[Appendix 4]
a second moving device provided on the support portion and configured to move the side surface suction portion in a direction approaching the side surface and in a direction away from the side surface,
When the luggage reaches the predetermined height at which the side suction portion does not interfere with the surroundings, the control device controls the second moving device to move the side suction portion to the side, and controls the holding device to cause the side suction portion to suction the side.
2. The unloading device of claim 1.
[Appendix 5]
On the computer,
a process of controlling a rotation device to hold a holding device having an upper surface suction portion that suctions an upper surface of the luggage, in a state in which a support portion that supports the holding device rotatably around a single axis that intersects in the vertical direction is maintained in an initial position in which the upper surface suction portion is approximately horizontal, and controlling the holding device to hold the luggage;
a process of controlling a first moving device connected to the support section and moving the support section to raise the support section to a predetermined height, and then controlling the rotating device to maintain the support section at the rotated position, and controlling the first moving device to move the luggage with a lower end of the luggage in contact with a placement surface for the luggage;
An unloading program that executes the following:
[Appendix 6]
a rotation device is controlled to hold the holding device having an upper surface suction portion that suctions an upper surface of the luggage, while a support portion that supports the holding device rotatably around a single axis that intersects in the vertical direction is maintained in an initial position in which the upper surface suction portion is substantially horizontal, and the holding device is controlled to hold the luggage;
a first moving device connected to the support section and moving the support section is controlled to raise the support section to a predetermined height, and then, in a state in which the support section is maintained at the rotated position by controlling the rotating device, the first moving device is controlled to move the luggage with a lower end of the luggage in contact with a placement surface of the luggage.
Unloading method.

2...luggage, 5...anti-slip agent, 5b...rear surface, 6...upper surface, 10...unloading device, 30...intermediate conveyor, 40...lifting device, 70...holding device, 71...upper surface suction portion, 72...side surface suction portion, 74...first suction pad, 76...second suction pad, 77...negative pressure generating device, 80...support portion, 81...support portion main body, 82...connecting portion, 83...first part, 84...second part, 85...bracket, 86...rotating shaft, 90...first moving device, 91...horizontal moving device, 92...lifting device, 93...base, 94...arm, 95...movable portion, 95a...forward/rearward actuator, 95 b...width direction actuator, 96...shaft, 97...vertical direction actuator, 98...wire, 110...second moving device, 111...base, 112...moving part, 113...third driving part, 120...rotating device, 121...arm, 122...rotating actuator, 123...cylinder, 124...piston, 125...pump, 126...circuit, 130...control device, 131...communication interface, 132...processor, 133...memory, 134...storage, 135...bus line, 140...third sensor, A1...initial position, A2...rotation position.

Claims (5)

A holding device including an upper surface suction portion that suctions an upper surface of the luggage and a side surface suction portion that suctions a side surface of the luggage;
a sensor for detecting whether the side suction portion interferes with the surroundings;
a support portion that supports the holding device so as to be rotatable about a single axis that intersects with the vertical direction;
A first moving device connected to the support and configured to move the support;
a second moving device provided on the support portion and configured to move the side suction portion in a direction approaching the side surface of the luggage and in a direction away from the side surface;
a rotation device that maintains the support portion at a rotation position around the single axis where the upper surface suction portion has moved downward from an initial position where the upper surface suction portion is substantially horizontal to a rotation position where the upper surface suction portion has moved downward from the initial position;
a control device that controls the holding device, the sensor, the first moving device, the second moving device, and the rotating device;
Equipped with
The control device includes:
when the upper surface suction portion of the holding device is controlled to hold the load by the upper surface suction portion while the pivot device is controlled to maintain the support portion at the initial position, the sensor detects whether or not the side surface suction portion will interfere with the surroundings when the second moving device is controlled to move the side surface suction portion toward the side surface of the load ,
When it is determined by the detection of the sensor that the side suction parts may interfere with the surroundings, the first moving device is controlled to raise the luggage to a predetermined height at which the side suction parts do not interfere with the surroundings ,
When the luggage reaches the predetermined height at which the side suction portion does not interfere with the surroundings, the second moving device is controlled to move the side suction portion to the side, and the holding device is controlled to cause the side suction portion to suction the side of the luggage,
Then, the rotation device is controlled to tilt the support portion from the initial position to the rotation position;
With the support portion maintained at the pivot position, the first moving device is controlled to move the luggage in a state in which a lower end of the luggage is in contact with a placement surface of the luggage .
Unloading equipment. The unloading device according to claim 1, wherein the control device controls the first moving device to raise the support part and the luggage in a direction intersecting the up-down direction. The unloading device according to claim 2, wherein the intersecting direction is a direction from the side suction portion toward the luggage side as it goes upward. On the computer,
a process of controlling a rotation device to support a holding device having an upper surface suction portion that suctions an upper surface of the luggage and a side surface suction portion that suctions a side surface of the luggage so as to be rotatable about a single axis intersecting in the vertical direction, while maintaining the upper surface suction portion in an initial position where the upper surface suction portion is approximately horizontal, and controlling the upper surface suction portion of the holding device to hold the luggage with the upper surface suction portion ;
a process of detecting, by a sensor, whether or not the side suction portion will interfere with the surroundings when attempting to move the side suction portion toward the side of the luggage by controlling a second moving device that is provided on the support portion and that moves the side suction portion in a direction approaching the side of the luggage and in a direction away from the side;
a process of controlling a first moving device connected to the support section and moving the support section when it is determined by the detection of the sensor that the side suction section may interfere with the surroundings, thereby lifting the luggage to a predetermined height at which the side suction section will not interfere with the surroundings ;
When the luggage reaches the predetermined height at which the side suction portion does not interfere with the surroundings, the second moving device is controlled to move the side suction portion to the side, and the holding device is controlled to cause the side suction portion to suction the side of the luggage;
Then , a process of controlling the rotation device to tilt the support portion from the initial position to a rotation position where the upper surface suction portion has moved downward from the initial position ;
a process of controlling the first moving device to move the luggage in a state where a lower end of the luggage is in contact with a placement surface of the luggage while the support portion is maintained at the rotation position ;
An unloading program that executes the following: a rotation device is controlled to maintain a support section that supports a holding device having an upper surface suction section that suctions an upper surface of the luggage and a side surface suction section that suctions a side surface of the luggage so as to be rotatable about a single axis that intersects in the vertical direction, in an initial position in which the upper surface suction section is substantially horizontal, and the upper surface suction section of the holding device is controlled to hold the luggage with the upper surface suction section ;
a second moving device is provided on the support portion and moves the side suction portion in a direction approaching the side surface of the luggage and in a direction away from the side surface, and when the side suction portion is moved toward the side surface of the luggage by controlling the second moving device, a sensor is used to detect whether the side suction portion will interfere with the surroundings;
when it is determined by the detection of the sensor that the side suction portions may interfere with the surroundings, a first moving device connected to the support portion and moving the support portion is controlled to raise the luggage to a predetermined height at which the side suction portions do not interfere with the surroundings ;
When the luggage reaches the predetermined height at which the side suction portion does not interfere with the surroundings, the second moving device is controlled to move the side suction portion to the side, and the holding device is controlled to cause the side suction portion to suction the side of the luggage,
Then , the rotating device is controlled to tilt the support portion from the initial position to a rotated position where the upper surface suction portion has moved downward from the initial position ,
With the support portion maintained at the pivot position , the first moving device is controlled to move the luggage with a lower end of the luggage in contact with a placement surface of the luggage.
Unloading method.