Conveying system

Abstract

When pulling in transported items from the placement surface and dispensing them to the installation surface, sufficient space must be ensured for the articulated robot to move to avoid contact with other equipment or other transported items. [Solution] The picking device 4 includes a platform 21 on which to be transported items P1 to P3 are placed, and a holding mechanism 50 including an arm 14 provided with a holding part 51 for holding the transported items P1 to P3. The picking device 4 also includes a drive mechanism 40 having an arm lifting mechanism 41 for raising and lowering the arm 14, and an arm linear motion mechanism 42B for moving the arm 14 horizontally with the retraction direction and discharge direction being horizontal. The arm 14 has an arm extension / retraction mechanism 42A that extends and retracts horizontally by slidably connecting a plurality of arm components, namely a head arm 14A and an intermediate arm 14B, along the horizontal direction.

Description

Technical Field

[0001] The present invention relates to a conveying system for conveying conveyed items.

Background Art

[0002] For example, as this type of technology, a robot hand (conveying system) for conveying conveyed items is disclosed. In this technology, the conveying system has a pad that adsorbs to the side surface of the conveyed item, a suction head that moves in the first direction, a drive belt that moves a conveying surface on which the conveyed item is placed, and a multi-joint robot having the suction head and the drive belt attached to its tip. In this technology, by driving the multi-joint robot to move the suction head in the first direction, the conveyed item adsorbed to the pad is placed on the conveying surface, and the conveyed item is conveyed by the drive belt.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in the conveying system of Patent Document 1, when pulling in the conveyed item from the placement surface and when paying out the conveyed item to the installation surface, a sufficient movable space of the multi-joint robot must be secured so as not to contact other devices or other conveyed items.

[0005] The present invention has been made in view of such points, and provides a conveying system that can suppress the required space when pulling in the conveyed item from the placement surface and when paying out the conveyed item to the installation surface, and can convey the conveyed item smoothly and quickly.

Means for Solving the Problems

[0006] In view of the above problems, the present invention provides a transport system for transported goods comprising: a trolley that autonomously travels a route from a transport start point to a transport destination point for transported goods; and a picking device attached to the trolley that pulls in the transported goods at the transport start point and dispenses the transported goods at the transport destination point. The picking device comprises: a platform on which the transported goods are placed; a holding mechanism including an arm provided with a holding part for holding the transported goods; an arm lifting mechanism for raising and lowering the arm; and a drive mechanism having an arm linear motion mechanism for moving the arm in the horizontal direction, with the pull-in and dispenser directions of the transported goods being horizontal. The arm is characterized by having an arm extension and retraction mechanism that extends and retracts in the horizontal direction by slidably connecting a plurality of arm parts to each other along the horizontal direction.

[0007] According to the present invention, the arm can be extended by connecting multiple arm components in a horizontally slidable manner using an arm extension mechanism. This allows for smooth and rapid pulling of items at the transport starting point and dispensing of items at the transport destination point, while minimizing the space required for the movement of the picking device.

[0008] In a more preferred embodiment, the holding portion is a suction head with multiple pads attached that adsorb the conveyed item by air suction, and the arms are provided in a pair, flanking the suction head. In this embodiment, even if a bending moment acts on the arms due to the weight of the suction head when the arms are extended, the bending moment is absorbed by the pair of arms, thus suppressing the deflection of the arms. As a result, misalignment of the suction head relative to the conveyed item can be suppressed.

[0009] In a more preferred embodiment, the suction head is equipped with a side pad for suctioning the side of the conveyed item and a top pad for suctioning the top surface of the conveyed item. In this embodiment, depending on the arrangement of the conveyed item, either the side pad or the top pad can be selected to suction the conveyed item and pull it onto the mounting table.

[0010] In this case, if the height of the placement surface on which the transported items are placed and the height of the installation surface on which the transported items are set are approximately the same, the height of the mounting platform is the same, and therefore the mounting platform may be fixed to the picking device without raising or lowering it. However, in a more preferred embodiment, the moving mechanism further includes a platform lifting mechanism for raising and lowering the mounting platform described above.

[0011] According to this embodiment, by using a platform lifting mechanism, even if the height of the placement surface and the installation surface of the transported item are different, the platform can be raised and lowered according to the height of the placement surface of the transported item at the transport starting point and the height of the installation surface of the transported item at the transport destination point. This allows the transported item to be smoothly drawn onto the platform, unloaded from the platform, and quickly installed on the installation surface.

[0012] Here, if the distance between the placement surface and the mounting surface of all transported items is the same for all transported items, the platform only needs to be raised and lowered by the platform lifting mechanism. However, in a more preferable embodiment, the drive mechanism further includes a platform linear motion mechanism that moves the platform described above in the horizontal direction relative to the platform lifting mechanism.

[0013] According to this embodiment, the platform can be moved horizontally by the platform linear motion mechanism to match the distance from the platform lifting mechanism to the surface on which the transported item is placed. This allows the platform to be brought closer to the surface on which the transported item is placed, and the transported item can be smoothly drawn onto the platform. Furthermore, the platform can be brought closer to the installation surface on which the transported item is to be placed, the transported item can be dispensed from the platform, and the transported item can be quickly installed on the installation surface.

[0014] The above-described series of operations may be performed manually by an operator, but in a more preferred embodiment, the transport system further comprises a control device that controls the suction of the pad by the suction head, the movement of the arm by the drive mechanism, and the extension and retraction of the arm by the arm extension mechanism. The control device controls the arm linear motion mechanism and the arm extension mechanism to move the arm and extend the arm so that the top surface pad faces the top surface of the transported item at the transport start point, controls the arm lifting mechanism and the suction head so that the top surface pad is attracted to the top surface of the transported item, controls the arm lifting mechanism so that the transported item is lifted while the top surface pad is attracted to the top surface, and controls the arm linear motion mechanism and the arm extension mechanism to move the arm and retract the arm so that the arm is moved and retracted so that the transported item is positioned above the mounting surface of the stand described above.

[0015] In this embodiment, the control device can move and extend the arm until the top pad is facing the top surface of the item being transported. Then, the top pad is attached to the top surface of the item being transported, and in this state, the item can be lifted and pulled up to above the mounting surface of the mounting platform. In this way, even if, for example, another item is located below and in front of the item being transported, the item can be smoothly placed on the mounting platform without its bottom surface being dragged on the top surface of the other item. [Effects of the Invention]

[0016] According to the present invention, the space required when pulling the transported items from the placement surface and when discharging the transported items to the installation surface is reduced, enabling smooth and rapid transport of the transported items. [Brief explanation of the drawing]

[0017] [Figure 1] This is a schematic perspective view of a transport system according to an embodiment of the present invention. [Figure 2] Figure 1 is a schematic perspective view of the transport system with its arm extended. [Figure 3] It is a block diagram of the conveying system shown in FIG. 1. [Figure 4] It is a block diagram of the control device shown in FIG. 2. [Figure 5] It is a control flowchart of the drawing-in of the conveyed item by the control device shown in FIG. 3. [Figure 6A] (a) to (d) are diagrams for explaining the drawing-in operation of the conveyed item. [Figure 6B] (a) to (d) are diagrams for explaining the drawing-in operation of the conveyed item following FIG. 6A(d). [Figure 6C] (a) to (d) are diagrams for explaining the drawing-in operation of the conveyed item following FIG. 6B(d). [Figure 6D] (a) to (c) are diagrams for explaining the drawing-in operation of the conveyed item following FIG. 6C(d). [Figure 7] It is a control flowchart of the payout of the conveyed item by the control device shown in FIG. 3. [Figure 8A] (a) to (d) are diagrams for explaining the payout operation of the conveyed item. [Figure 8B] (a) to (d) are diagrams for explaining the payout operation of the conveyed item following FIG. 8A(d).

Embodiments for Carrying Out the Invention

[0018] Hereinafter, the conveying system 1 according to the embodiment of the present invention will be described while referring to FIGS. 1 to 8B.

[0019] 1. Regarding the conveying system 1 The transport system 1 according to this embodiment is a system that, at the transport starting point, pulls in (takes in) transport items P1 to P3, etc., which are placed on the placement surface of shelf C (described later with reference to Figure 6A, etc.), and transports the taken transport items P1 to P3, etc. Furthermore, the transport system 1 is a system that, at the transport destination point (described later with reference to Figure 8A, etc.), dispenses the transport items P1 to P3, etc., and places them on the installation surface of frame-shaped shelf C. In the following specification, the surface on which the transport items P1 to P3, etc. are placed at the transport placement point is referred to as the placement surface, and the surface on which the transport items P1 to P3, etc. are installed at the transport destination point is referred to as the installation surface. The placement surface and the installation surface are planes on which the bottom surface of the transport items comes into contact, and are not limited to continuous planes, but also include intermittent planes such as the surface of a pallet.

[0020] Furthermore, the transported items are rectangular packaging boxes (for example, cardboard boxes) containing parts such as machine parts, but the shape of the transported items P1 to P3, etc. is not particularly limited, as long as the sides Pb and top surface Pt of the transported items P1 to P3, etc., described later can be adsorbed by the side pads 52A and top surface pads 52B, described later.

[0021] In this embodiment, as shown in Figure 1, the transport system 1 comprises at least a trolley 2 that autonomously travels a route from a transport starting point to a transport destination point for transported items P1 to P3, and a picking device 4 attached to the trolley 2 that pulls in transported items P1 to P3, etc. at the transport starting point and dispenses transported items P1 to P3, etc. at the transport destination point.

[0022] 2. Regarding trolley 2 The trolley 2 is equipped with a picking device 4 and is a device that transports items P1 to P3, etc., together with the picking device 4. As shown in Figure 1, for example, the trolley 2 can move in all directions, not just in the two orthogonal directions LA and LB on the floor surface, and furthermore, it can rotate in the rotational direction T without substantially moving on the floor surface. Such a trolley 2 is a so-called self-supporting transport trolley, and its drive mechanism and other components have a general structure, so a detailed explanation will be omitted.

[0023] Although not shown in Figure 1, the transport system 1 is equipped with a control device 70 (see Figure 2). The control device 70 stores, for example, a map of the areas in the factory or warehouse where the trolley 2 can travel. For example, the control device 70 receives information such as the transport start point, transport destination point, and transport item information (size, placement, and installation location of transport items P1-P3, etc.) via wireless signals from an external management computer. The control device 70 sets the optimal travel route from the transport start point to the transport destination point. The trolley 2 travels along this route using automatic travel control. By controlling the rotation of the trolley 2, the orientation of the trolley 2 is also controlled to match the placement and installation locations of the transport items P1-P3, etc.

[0024] In this embodiment, the transport start point and the transport destination point may be different locations, but they may also coincide. For example, when transporting items P1 to P3 etc. in the vertical direction of the same shelf C without driving the trolley 2, or when the trolley 2 of the transport system 1 is rotated and placed on a shelf C in a different direction, the transport start point and the transport destination point will coincide.

[0025] 3. Regarding picking device 4 The picking device 4 is mounted on a trolley 2. The picking device 4 includes a placement device 20 equipped with a placement table 21 on which to be transported items P1 to P3, etc., and a holding mechanism 50 including an arm 14 equipped with a holding part (suction head 51) for holding the to be transported items P1 to P3, etc. The picking device 4 further includes a drive mechanism 40 for driving the placement device 20 and the holding mechanism 50, and a storage mechanism 60 equipped with racks 61 to 63 arranged at intervals in the vertical direction. Although not shown in Figures 1 and 2, the picking device 4 further includes an imaging device 8 for imaging the to be transported items P1 to P3, etc. (see Figure 3).

[0026] In this embodiment, as shown in Figures 1 and 2, the picking device 4 has a pair of support columns 11, 11 extending vertically from the trolley 2, and the upper ends of the pair of support columns 11, 11 are connected by an upper beam 12. As a result, the pair of support columns 11, 11 and the upper beam 12 form a gate-shaped support that supports the arm 14, the mounting platform 21, etc. Between the pair of support columns 11, 11, the arm 14 and the mounting platform 21 of the picking device 4 are attached to the support columns 11 so as to be able to move up and down.

[0027] 3-1. Regarding the mounting device 20 The loading device 20 includes a loading platform 21. In this embodiment, the loading platform 21 is equipped with a roller conveyor 45 that transports the items P1 to P3, etc., along the horizontal direction. The roller conveyor 45 is driven by a platform conveyor motor 45a shown in Figure 3. This allows the items P1 to P3, etc., placed on the loading platform 21 to be transported along the inward and outward directions. In this embodiment, a roller conveyor 45 is used as an example, but the transport configuration is not particularly limited as long as it is a transport conveyor capable of transporting the items P1 to P3. For example, a belt conveyor may be used instead of the roller conveyor 45.

[0028] The mounting platform 21 is supported by a support body 22. The carriage of the platform lifting mechanism 43, which will be described later, is attached to the support body 22, and is movable vertically (in the Z-axis direction) along the support column 11. Furthermore, as will be described later, a platform linear motion mechanism 44 is provided between the mounting platform 21 and the support body 22 to move the mounting platform 21 horizontally relative to the platform lifting mechanism 43. This makes it possible to move the mounting platform 21 horizontally in the retraction direction and the extension direction.

[0029] Furthermore, a contact sensor (contact detection sensor) 59B is provided at the tip of the mounting base 21 to detect when the tip of the mounting base 21 comes into contact with another object (see, for example, Figure 3). Note that any sensor capable of detecting contact with the tip of the mounting base 21 (a contact detection sensor) may be used instead of the contact sensor 59B, such as a laser-type contact detection sensor. The detection method of the contact detection sensor may be the same as that of the force sensor 59A described later, and is not particularly limited as long as it can detect contact with the tip of the mounting base 21.

[0030] 3-2. Regarding the holding mechanism 50 The holding mechanism 50 has an arm 14 equipped with a holding portion for holding the conveyed items P1 to P3, etc. In this embodiment, the holding mechanism 50 is a suction mechanism, and the holding portion is a suction head 51 to which multiple side pads 52A and top pads 52B are attached, which are used to suction the conveyed items P1 to P3, etc. by air suction. Alternatively, the holding mechanism 50 may be a gripping mechanism that holds the conveyed items P1 to P3, etc. by gripping them with the tips of a pair of arms 14, 14. In this case, the holding portion is provided at the tips of the pair of arms and corresponds to a claw portion that grips the conveyed items P1 to P3, etc.

[0031] In this embodiment, a pair of arms 14 are provided, flanking the suction head 51. The suction head 51 is attached to the tip of each arm 14 (arm body). The suction head 51 is fitted with multiple side pads 52A for sucking the side surfaces Pb of the conveyed items P1 to P3, etc., and multiple top surface pads 52B for sucking the top surfaces Pt of the conveyed items P1 to P3, etc.

[0032] The holding mechanism is a mechanism that, at the transport start point and the transport destination point, uses the corresponding side pad 52A or top pad 52B to attract either the top surface Pt or side surface Pb of the transported items P1 to P3, etc., that are placed on the loading device 20.

[0033] Specifically, in this embodiment, multiple side pads 52A are arranged at intervals on the tip surface of the suction head 51 (for example, 2 rows x 5 pads = 10 pads). Each side pad 52A is positioned so that the suction direction is horizontal. The number of side pads 52A is not limited as long as they can attract the side Pb of the conveyed items P1 to P3 and move the conveyed items P1 to P3 by pulling them in.

[0034] On the other hand, multiple top pads 52B are arranged at intervals on the underside of the tip of the arm 14 (for example, 4 rows x 7 pads = 28 pads). Each top pad 52B is positioned so that its suction direction is vertically downward. The number of top pads 52B is not limited as long as they can pick up and move the transported items P1-P3, etc.

[0035] The side pads 52A and top pad 52B have a bellows-like, expandable shape, with the leading edge where the opening is formed serving as the suction surface. In this embodiment, the side pads 52A and top pad 52B are bellows-like, but the pads 52 may be sponge-like, for example, as long as stable suction is possible with the side pads 52A and top pad 52B, and are not limited to this form.

[0036] Furthermore, a force sensor 59A is provided at the base end of the side pad 52A and the top pad 52B as a detection sensor to detect contact between the leading edges of the side pad 52A and the top pad 52B (see, for example, Figure 3). Thus, the force sensor 59A is a sensor that detects the force (or contact pressure) when the side pad 52A and the top pad 52B contact the surface of the conveyed items P1 to P3, etc. The control device 70 determines that the pads 52 have come into contact with the conveyed items P1 to P3, etc., when the detected force (or pressure) exceeds a preset value.

[0037] Examples of force sensors 59A include general sensors such as piezoelectric elements and strain gauges. The detection method of the detection sensor is not particularly limited as long as it can detect contact between the leading edges of the side pads 52A and the top pad 52B. For example, the detection sensor may be a positioning sensor (proximity sensor) that measures the distance between the top surface Pt and side surface Pb of the conveyed items P1 to P3, etc., and the suction surfaces of the side pads 52A and the top pad 52B.

[0038] The side pads 52A and top pad 52B are connected to the suction pump 54 via a pressure regulating valve 55 and a switching valve (three-way valve) 56. The control device 70 can switch the switching valve 56 to selectively generate negative pressure inside the side pads 52A or top pad 52B that are in contact with the conveyed items P1-P3, etc., using air drawn in by the suction pump 54. This allows the pads 52 to be attracted to the side Pb or top Pt of the conveyed items P1-P3, etc.

[0039] The pressure at this time is regulated by the pressure regulating valve 55, and the generated suction pressure (negative pressure) is detected by the pressure gauge 58. The pressure signal detected by the pressure gauge 58 is transmitted to the control device 70. A relief valve 57 is provided in the piping branched from the piping connecting the pressure regulating valve 55 and the switching valve 56, which connects the inside of the pad 52 to the atmosphere. When the suction of the pad 52 is released, the suction pump 54 is stopped and the relief valve 57 is opened by a control signal from the control device 70. As a result, air flows into the pad 52 through the relief valve 57, and the negative pressure inside the pad 52 is released to atmospheric pressure.

[0040] In this embodiment, a pair of arms 14 (specifically, the head arm 14A described later) are attached to the suction head 51 at their tip ends so as to sandwich the suction head 51. Each arm 14 is attached to a support body 13 at its base end. The support body 13 has a structure in which a connecting member 13c is connected to a pair of horizontally extending support arms 13b, 13b. Each arm 14 is slidable horizontally by an arm linear motion mechanism (slide mechanism) 42B. By driving the intermediate arm linear motion motor 42b shown in Figure 3, the arms 14 can be slid relative to the support body 13.

[0041] Each arm 14 has multiple (two) arm components, namely a head arm 14A and an intermediate arm 14B. The head arm 14A and the intermediate arm 14B are connected to each other so as to be slidable horizontally. In this embodiment, the head arm 14A is slidable horizontally by an arm extension / retraction mechanism (sliding mechanism) 42A provided on the intermediate arm 14B.

[0042] Specifically, by driving the head arm linear motor 42a shown in Figure 3, the head arm 14A can be slid relative to the intermediate arm 14B. This allows the arm 14 to extend and retract horizontally. In this way, the suction head 51 can be moved horizontally in two stages by moving the arm 14 and extending and retracting the arm 14. In this embodiment, one intermediate arm 14B is provided for one arm 14, but by further providing an intermediate arm that is slidably connected to it, the suction head 51 may be moved horizontally in three or more stages.

[0043] 3-3. About the storage mechanism 60 In this embodiment, the storage mechanism 60 includes racks 61 to 63 arranged at intervals in the vertical direction. Specifically, each rack 61 to 63 is attached to a pair of support columns 11, 11 via a mounting plate 65 on the rear side of the picking device 4 (specifically, the rear side in the dispensing direction). Each rack 61 to 63 temporarily stores the transported items P1 to P3, etc., with them placed on top. Each rack 61 to 63 is inclined downward toward the rear in the dispensing direction. This allows the transported items P1 to P3, etc., transported from the loading platform 21 to be smoothly transported to the racks 61 to 63.

[0044] Each rack 61-63 is equipped with a roller conveyor 46 that transports items P1-P3, etc., horizontally. The roller conveyor 46 is driven by a rack conveyor motor 46a shown in Figure 3. This allows items P1-P3 to be transported from the mounting table 21 to each rack 61-63. In this embodiment, a roller conveyor 45 is used as an example, but the transport configuration is not particularly limited as long as it is a transport conveyor that transports items P1-P3. A belt conveyor may be used instead of the roller conveyor 45. Around the roller conveyor 46, there are drop prevention plates 64 to prevent items P1-P3, etc. from falling.

[0045] 3-4. Regarding the drive mechanism 40 The drive mechanism 40 is a mechanism that moves the arm 14 and the mounting platform 21, etc., along the X and Z axes. As shown in Figure 1, etc., the X, Y, and Z axes are mutually orthogonal axes. The X axis is the axis along the direction in which the transported items P1 to P3, etc., are pulled in and discharged from the trolley 2. The Y axis is the axis along the horizontal direction perpendicular to the X axis. The Z axis is the axis along the vertical direction, that is, the direction in which the transported items P1 to P3, etc., are raised and lowered. The drive mechanism 40 will be described below with reference to Figures 1 and 2.

[0046] Specifically, the drive mechanism 40 includes an arm lifting mechanism 41 that raises and lowers the arm 14 in the vertical direction (i.e., the Z-axis direction), and an arm linear motion mechanism 42B that moves the arm 14 horizontally, with the retraction direction and extension direction (i.e., the X-axis direction) being horizontal.

[0047] The arm lifting mechanism 41 is a mechanism that raises and lowers the arm 14 in the Z-axis direction by driving the arm lifting motor 41a shown in Figure 3. The arm lifting mechanism 41 is a linear guide mechanism and is connected to the arm lifting motor 41a and comprises a shaft (not shown) with screw grooves formed on its circumferential surface, and a pair of guide rails (not shown) arranged parallel to the shaft. The shaft and guide rails extend in the Z-axis direction, and the shaft rotates around the Z-axis. These components are installed while housed within the support column 11. The arm lifting mechanism 41 further comprises a carriage, which is screwed onto the shaft and slidably connected to the pair of guide rails.

[0048] When raising or lowering the arm 14, the arm lifting motor 41a is driven by a control signal from the control device 70, causing the shaft to rotate around the Z-axis. This allows the carriage, which is screwed onto the shaft, to move together with the arm 14 in the vertical direction (Z-axis direction) along the guide rail.

[0049] The arm linear motion mechanism 42B is a mechanism that moves the arm 14 horizontally along the X-axis direction by driving the intermediate arm linear motion motor 42b. The arm linear motion mechanism 42B is a linear guide mechanism similar to that of the arm lifting mechanism 41. The arm linear motion mechanism 42B includes a shaft (not shown) and a pair of guide rails (not shown) extending along the X-axis direction within the support body 13. The shaft is connected to the intermediate arm linear motion motor 42b via a power transmission belt or the like. The arm linear motion mechanism 42B further includes a carriage (not shown), which is screwed onto the shaft and slidably connected to the pair of guide rails. The support body 13 is fixed to the carriage of the arm lifting mechanism 41.

[0050] When moving the arm 14 linearly along the X-axis, the control signal from the control device 70 drives the intermediate arm linear motor 42b, rotating the shaft around the X-axis. This allows the carriage screwed onto the shaft to move horizontally (in the X-axis direction) along the guide rail, together with the arm 14.

[0051] In this embodiment, in addition to the drive mechanism 40, an arm extension / retraction mechanism 42A is provided that extends and retracts the arm 14 horizontally (extends and retracts the arm 14 longitudinally). The arm extension / retraction mechanism 42A is a mechanism that moves the head arm 14A horizontally relative to the intermediate arm 14B along the X-axis direction by driving the intermediate arm linear motor 42b. The intermediate arm linear motor 42b is a linear guide mechanism similar to that of the arm lifting mechanism 41. The arm extension / retraction mechanism 42A includes a shaft (not shown) and a pair of guide rails (not shown) that extend along the X-axis direction within the intermediate arm 14B. The shaft is connected to the intermediate arm linear motor 42b via a power transmission belt or the like. The intermediate arm linear motor 42b further includes a carriage (not shown), which is screwed onto the shaft and slidably connected to the pair of guide rails.

[0052] When extending or retracting the arm 14 along the X-axis, the control signal from the control device 70 drives the intermediate arm linear motor 42b, rotating the shaft around the X-axis. This allows the carriage screwed onto the shaft to move horizontally (in the X-axis direction) along the guide rail, together with the head arm 14A.

[0053] The drive mechanism 40 further includes a platform lifting mechanism 43 for raising and lowering the mounting platform 21, and a platform linear motion mechanism 44 for moving the mounting platform 21 horizontally. The platform lifting mechanism 43 is a mechanism that raises and lowers the mounting platform 21 in the Z-axis direction by driving a platform lifting motor 43a. The platform linear motion mechanism 44 is a mechanism that moves the mounting platform 21 in the X-axis direction (horizontal direction) by driving a platform linear motion motor 44a. The platform lifting mechanism 43 is a linear guide mechanism arranged in parallel with the arm lifting mechanism 41 in the Z-axis direction (vertical direction) within the support column 11, and the platform linear motion mechanism 44 is a linear guide mechanism housed within the support body 22. Since the details of these mechanisms are the same as those of the arm lifting mechanism 41 and the arm linear motion mechanism 42B, a detailed explanation will be omitted.

[0054] When raising or lowering the mounting platform 21, a control signal from the control device 70 drives the platform lifting motor 43a, rotating the shaft (not shown) of the platform lifting mechanism 43 around the Z-axis. This allows the carriage of the platform lifting mechanism 43, which is screwed onto the shaft, to move together with the mounting platform 21 in the vertical direction (Z-axis direction) along the guide rail (not shown) of the platform lifting mechanism 43. In this way, the arm lifting mechanism 41 and the platform lifting mechanism 43 allow the arm 14 and the mounting platform 21 to be raised and lowered independently.

[0055] Furthermore, when moving the mounting base 21 in a linear motion horizontally, a control signal from the control device 70 drives the base linear motion motor 44a, rotating the shaft (not shown) of the base linear motion mechanism 44 around the X-axis. This allows the carriage (not shown) of the base linear motion mechanism 44, which is screwed onto the shaft, to move together with the mounting base 21 in the vertical direction (Z-axis direction) along the guide rail (not shown). In this way, the arm linear motion mechanism 42B and the base linear motion mechanism 44 allow the arm 14 and the mounting base 21 to move horizontally independently.

[0056] 4. Regarding the control device 70 The control device 70 will be described below with reference to Figures 4 to 8B. The control device 70 controls the suction of the side pads 52A and top pad 52B by the suction head 51, the movement of the arm 14 by the drive mechanism 40, and the extension and retraction of the arm 14 by the arm extension / retraction mechanism 42A. In this embodiment, the control device 70 also performs automatic travel control of the trolley 2, and further controls the drive of the roller conveyors 45 and 46 of the mounting platform 21 and racks 61 to 63.

[0057] The control device 70, as hardware, includes a memory device and a processing unit, although these are not shown in the diagram. The memory device stores a travel map of the warehouse or factory where the trolley travels, operation programs for operating the drive mechanism 40 and the holding mechanism 50, etc. The processing unit calculates the travel route from the travel map and makes decisions on whether to activate the operation programs, etc.

[0058] Specifically, as shown in Figure 4, the control device 70 includes, as software, a trolley travel control unit 71, a conveyed item detection unit 72, an arm lifting control unit 73, an arm movement extension / retraction control unit 74, a platform lifting control unit 75, a platform movement control unit 76, a suction control unit 77, and a conveyor control unit 78. These will be explained along with the following control flow.

[0059] 4-1. Control flow for the suction of transported items P1~P3, etc. The pull-in control by the control device 70 will be explained below with further reference to Figures 2 to 4 and Figures 5 to 6D. As shown in Figure 5, in step S501, the trolley 2 of the transport system 1 is controlled to move the trolley 2 to the transport start point where the transport items P1 to P3 are placed (see Figure 6A(a)). The transport items P1 to P3 are placed on shelf C at the transport start position. Specifically, as shown in Figure 4, the trolley travel control unit 71 sets the transport route for the trolley 2 to the transport start point based on the transport start point and information on the transport items P1 to P3 (specifically, the size of the transport items P1 to P3, the height of the placement surface, etc.) input from the input device 7, as well as the position information of the trolley 2, and controls the drive device (not shown) of the trolley 2. Next, upon receiving a detection signal from the trolley travel control unit 71 that the trolley has reached the transport start point, the transport item detection unit 72 detects the positions of the transport items P1 to P3 at the transport start point.

[0060] Next, the process proceeds to step S502, where the control device 70 determines, based on the image captured by the imaging device 8, whether or not there are other transported items (articles) in front of and below the transported item P1. In Figure 6A(a), it is determined that there are no articles (No) in front of and below the transported item P1. In this case, the process proceeds to step S503, where suction by the side pads 52A is selected, and the process proceeds to step S504.

[0061] Next, in step S504, as shown in Figure 6A(b), the control device 70 raises and lowers the arm 14 and the mounting platform 21 according to the height H1 of the surface on which the transported item P1 is placed. Specifically, the arm lifting control unit 73 controls the arm lifting motor 41a of the arm lifting mechanism 41 so that the Z-axis position of the side pad 52A is located in the center of the side surface of the transported item P1, in accordance with the detected height H1 of the surface on which the transported item P1 is placed. Furthermore, the platform lifting control unit 75 controls the platform lifting motor 43a of the platform lifting mechanism 43 so that the height of the mounting surface of the mounting device 20 is the same as the height H1 of the surface on which the transported item P1 is placed. These motor controls are performed based on detection signals from encoders attached to each of the motors 41a and 43a so that the side pad 52A and the mounting platform 21 are at the target height.

[0062] Next, in step S505, as shown in Figure 6A(c), the arm movement extension / retraction control unit 74 controls the head arm linear motor 42a of the arm extension / retraction mechanism 42A so that the suction head 51 moves (advances) toward the conveyed item P1. Alternatively, the intermediate arm linear motor 42b of the arm linear motor mechanism 42B may be controlled to move the entire arm 14. In conjunction with this, the base movement control unit 76 controls the base linear motor 44a of the base movement control unit 76 so that the mounting base 21 moves (advances) toward the conveyed item P1.

[0063] Next, the process proceeds to step S506, where the contact sensor 59B described above determines whether the leading edge of the forward-moving platform 21 has come into contact with another object. If the platform movement control unit 76 determines that the platform 21 has not come into contact with another object (No), it returns to step S505 and continues the movement (forward movement) of the platform 21. On the other hand, if the platform movement control unit 76 determines that the platform 21 has come into contact with another object (Yes), it stops the drive of the platform linear motor 44a and proceeds to step S507.

[0064] Next, the process proceeds to step S507, where the force sensor 59A determines whether the side pad 52A has made contact with the side Pb of the conveyed item P1. If the arm movement extension / retraction control unit 74 determines that the side pad 52A has not made contact with the side Pb of the conveyed item P1 (No), it returns to step S505 and continues the movement (forward movement) of the suction head 51 toward the conveyed item P1. In this state, the base linear motor 44a remains stopped. On the other hand, if the arm movement extension / retraction control unit 74 determines that the side pad 52A has made contact with the side Pb of the conveyed item P1 (Yes), it stops the drive of the head arm linear motor 42a and proceeds to step S508.

[0065] In step S508, upon receiving drive stop signals from the head arm linear motor 42a and the base linear motor 44a, the suction control unit 77 starts the suction pump 54. As a result, negative pressure is generated inside the side pad 52A. The suction control unit 77 continues suction until the suction pressure (negative pressure) measured by the pressure gauge 58 falls below a predetermined pressure.

[0066] Next, in step S509, as shown in Figure 6A(d), the arm movement extension control unit 74 controls the head arm linear motor 42a to pull in the transported item P1 while the side pads 52A are attached to the side Pb of the transported item P1. This allows the transported item P1 to be placed on the mounting table 21. In this embodiment, the mounting table 21 is moved horizontally, and the tip of the mounting table 21 can be brought close to the transported item P1, so that the transported item P1 can be smoothly placed on the mounting table 21. After the transported item P1 is pulled onto the mounting table 21, the suction by the side pads 52A is released.

[0067] Next, in step S510, as shown in Figure 6B(a), the arm movement extension control unit 74 and the base movement control unit 76 control the head arm linear motor 42a and the base linear motor 44a to pull the transported item P1 together with the mounting base 21. Next, proceeding to step S511, as shown in Figure 6B(b), the base lifting control unit 75 controls the base lifting motor 43a so that the mounting base 21 on which the transported item P1 is placed descends to the height of the rack 63.

[0068] Next, the process proceeds to step S512, where the conveyor control unit 78 controls the base conveyor motor 45a and the rack conveyor motor 46a so that the transported item P1 moves from the base 21 to the rack 63. This drives the roller conveyors 45 and 46, allowing the transported item P1 to be stored in the rack 63.

[0069] In steps S511 and S512, if there is an item P2 to be transported, the arm lifting control unit 73 may control the arm lifting motor 41a to raise or lower the arm 14 to a height corresponding to the next item P2 to be transported. In this embodiment, since the mounting base 21 and the arm 14 can be raised and lowered independently, the arm 14 can be operated simultaneously while the mounting base 21 operates in steps S511 and S512.

[0070] In such cases, in steps S511 and S512, the storage operation by the mounting platform 21 is performed, and the process returns to step S502. Specifically, the control device 70 determines whether or not there is another item being transported below the front of the transported item P2 based on the results captured by the imaging device 8. In step S502, as shown in Figure 6B(b), the control device 70 determines that there is an item below the front of the transported item P2 (Yes). In this case, pulling the transported item P2 horizontally with the side pad 52A would cause the transported item P2 to slide along the top surface of the other transported items (articles) on the shelf C, which is undesirable. Therefore, the process proceeds to step S513, where suction by the top pad 52B is selected, and the process proceeds to step S514. In step S514, as shown in Figure 6B(b), the control device 70 raises and lowers the arm 14 according to the height H2 of the top surface of the transported item P2.

[0071] Specifically, the arm lifting motor 41a of the arm lifting mechanism 41 is controlled so that the Z-axis position of the lower surface (suction surface) of the top pad 52B is slightly higher than the height H2 of the top surface Pt of the transported item P2. Furthermore, as shown in Figure 6B(b), the platform lifting control unit 75 controls the platform lifting motor 43a of the platform lifting mechanism 43 so that the height of the mounting surface of the mounting platform 21 is slightly higher than the height H1 of the placement surface of the transported item P2 (specifically, the height of the lower part of the side surface Pb of the transported item P2). In this case, only the movement of the arm 14 may be performed in step S515 prior to the lifting movement of the mounting platform 21.

[0072] In step S515, as shown in Figure 6B(c), the arm movement extension control unit 74 extends the arm 14 and moves (advances) the arm 14 toward the transported item P2, controlling the intermediate arm linear motor 42b of the arm linear motion mechanism 42B and the head arm linear motor 42a of the arm extension mechanism 42A until the top pad 52B faces the top surface Pt of the transported item P2. Subsequently, in conjunction with this, the base movement control unit 76 controls the base linear motion motor 44a of the base linear motion mechanism 44 so that the mounting base 21 moves (advances) toward the side surface Pb (lower part) of the transported item P2.

[0073] Next, the process proceeds to step S516, where the contact sensor 59B determines whether the forward-moving platform 21 has made contact with the side surface Pb of the transported item P2. If the platform movement control unit 76 determines that the platform 21 has not made contact with the transported item P2 (No), it returns to step S515 and continues to move (forward) the platform 21. On the other hand, if the platform movement control unit 76 determines that the platform 21 has made contact with the transported item P2 (Yes), it stops driving the platform linear motor 44a and proceeds to step S517.

[0074] Next, in step S517, as shown in Figure 6B(c), the arm lifting control unit 73 controls the arm lifting motor 41a of the arm lifting mechanism 41 so that the top pad 52B descends toward the top surface Pt of the conveyed item P2 together with the arm 14. Next, the process proceeds to step S518, where the force sensor 59A, as described above, determines whether the top pad 52B has come into contact with the top surface Pt of the conveyed item P2. If the arm lifting control unit 73 determines that the pad 52 has not come into contact with the top surface Pt of the conveyed item P2 (No), it returns to step S517 and continues the descent of the arm 14 toward the conveyed item P2. On the other hand, if the arm movement extension control unit 74 determines that the pad 52 has come into contact with the top surface Pt of the conveyed item P2 (Yes), it stops driving the arm lifting motor 41a and proceeds to step S519.

[0075] Next, in step S519, upon receiving a drive stop signal for the arm lifting motor 41a from the arm lifting control unit 73, the suction control unit 77 switches via the switching valve 56 and starts the suction pump 54. This generates negative pressure inside the top pad 52B. The suction control unit 77 continues suction until the suction pressure (negative pressure) measured by the pressure gauge 58 falls below a predetermined pressure.

[0076] Next, in step S520, as shown in Figure 6B(d), the arm lifting control unit 73 controls the arm lifting motor 41a of the arm lifting mechanism 41 so that the transported item P2 is lifted while the top surface pad 52B is attached to the top surface Pt of the transported item P2. As a result, the transported item P2 is suspended in the air. Next, the intermediate arm linear motor 42b of the arm linear motor 42B and the head arm linear motor 42a of the arm extension mechanism 42A are controlled to move (retract) the arm 14 and retract the arm 14 until the transported item P2 is positioned above the mounting table 21.

[0077] Next, the arm lifting control unit 73 controls the arm lifting motor 41a of the arm lifting mechanism 41 until the transported item P2 descends toward the mounting table 21 and contacts the mounting table 21 based on the detection signal from the force sensor 59A. After that, the suction control unit 77 stops the suction pump 54 and opens the relief valve 57. As a result, the suction pressure of the pad 52 is released to atmospheric pressure (pressure release), and the suction of the top surface Pt of the transported item P2 by the top surface pad 52B is released. Since the tip of the mounting table 21 is positioned adjacent to the transported item P2, the transported item P2 can be quickly placed on the mounting table 21. Then, as in the case described above, in step S510, the control device 70 retracts the arm 14 and the mounting table 21 (see Figure 6C(a)). Subsequently, in step S511, the platform 21 is lowered to the rack 62, and in step S511, the transported item P2 is placed from the platform 21 to the rack 62 (see Figure 6C(b)).

[0078] Furthermore, when transporting the item P3 located on the lower level as shown in Figure 6C(c), the item P3 is stored in the rack 63 through a series of steps S502 to S513 described above (see Figures 6C(c) to 6D(c)). Here, as shown in Figure 6C(d), the distance W2 from shelf C (side) to side Pb of item P3 is longer than the distance W1 from shelf C (side) to side Pb of item P1 as shown in Figure 6A(a). Even in such a case, as shown in Figure 6D(a), by moving the mounting table 21 in the discharge direction using the linear movement mechanism 44 in steps S506 to S508, the mounting table 21 can be brought closer to the placement surface on which item P3 is placed. As a result, in step S510, item P3 can be smoothly pulled onto the mounting table 21 (see Figure 6D(a)). Subsequently, after step S511 (see Figures 6D(b) and (c)), the transported items P3 can be stored in the rack 61 by steps S512 and S513. In this embodiment, the transported items P1 to P3, which are placed on one shelf C, are taken from shelf C, but for example, the transported items may be taken from each of different shelves C.

[0079] 4-2. Dispensing control flow for transported item P1 The dispensing control by the control device 70 will be explained below with further reference to Figures 7 to 8B, along with Figures 2 to 4. First, as shown in Figure 7, in step S701, the trolley 2 of the transport system 1 is controlled to move the transport system 1 on which the transported item P1 is placed to the transport destination. Specifically, as shown in Figure 3, the trolley travel control unit 71 sets the transport route of the trolley 2 from the transport start point to the transport destination based on the transport start point, transport destination point, and information on the transported item P1 (specifically, the size of the transported item P1, the height H4 of the installation surface, etc.) input from the input device 7, and controls the drive device (not shown) of the trolley 2.

[0080] Next, in step S702, upon receiving a detection signal from the trolley travel control unit 71 indicating that the transport destination point has been reached, the platform lifting control unit 75 controls the platform lifting motor 43a of the platform lifting mechanism 43, as shown in Figure 8A(a), so that the height of the mounting surface of the mounting device 20 becomes the same height as the height of the mounting surface of the rack 63.

[0081] Next, in step S703, as shown in Figure 8A(b), the conveyor control unit 78 controls the table conveyor motor 45a and the rack conveyor motor 46a so that the transported item P1 moves from the rack 63 to the platform 21. This allows the transported item P1 to be placed on the platform 21. Then, proceeding to steps S704 and S705, the arm lifting control unit 73 controls the arm lifting motor 41a of the arm lifting mechanism 41 until the top surface pad 52B (or its suction surface) makes contact with the top surface Pt of the transported item P1 placed on the platform 21 (contact is detected by the force sensor 59A) (see Figures 8A(b) and 8A(c)).

[0082] Next, in step S706, the suction control unit 77 generates negative pressure inside the pad 52 while the pad 52 is in contact with the top surface Pt of the conveyed item P1. The suction control unit 77 continues suction using the suction pump 54 until the suction pressure (negative pressure) measured by the pressure gauge 58 falls below a predetermined pressure. In this state, in step S707, the arm lifting control unit 73 and the platform lifting control unit 75 raise the arm 14 and the platform 21 at the same speed (specifically, raise them).

[0083] Next, as shown in Figure 8A(d), in step S708, the arm movement extension control unit 74 moves the arm 14 forward while extending it toward the installation surface C1 to a position just in front of the installation surface C1. Specifically, the arm movement extension control unit 74 controls the intermediate arm linear motor 42b of the arm linear motion mechanism 42B and the head arm linear motor 42a of the arm extension mechanism 42A.

[0084] In step S709, as shown in Figure 8B(a), the arm lifting control unit 73 controls the arm lifting mechanism 41 so that the transported item P1, which is placed on the mounting base 21, is lifted while the top surface pad 52B is attached to the top surface Pt of the transported item P1. Specifically, the arm lifting control unit 73 controls the arm lifting motor 41a of the arm lifting mechanism 41 so that the height of the bottom surface of the lifted transported item P1 is higher than the height of the mounting surface of the mounting base 21 and the height of the installation surface C1. In this way, the arm lifting control unit 73 raises the top surface pad 52B and puts the transported item P1 in a suspended state.

[0085] Next, in step S710, as shown in Figure 8B(b), the arm movement extension control unit 74 extends the arm 14 and moves the arm 14 toward the mounting surface (forward), controlling the intermediate arm linear motor 42b of the arm linear mechanism 42B and the head arm linear motor 42a of the arm extension mechanism 42A until the top pad 52B is in a position facing the installation surface C1. In this way, the arm movement extension control unit 74 moves the top pad 52B in the X-axis direction, and moves the suspended transported product P1 above the installation surface C1. At this time, as shown in Figure 8B(b), the mounting base 21 may be retracted.

[0086] Next, in step S711, as shown in Figure 8B(c), the arm lifting control unit 73 controls the arm lifting motor 41a of the arm lifting mechanism 41 so that it moves (descends) toward the installation surface C1 of the transported item P1. Next, the process proceeds to step S712, where the force sensor 59A described above determines whether the transported item P1 has made contact with the installation surface C1. If the arm lifting control unit 73 determines that the transported item P1 has not made contact with the installation surface C1 (No), it returns to step S711 and continues moving (descending) the top pad 52B toward the transported item P1. On the other hand, if the arm lifting control unit 73 determines that the transported item P1 has made contact with the installation surface C1 (Yes), it stops driving the arm lifting motor 41a. At this time, as shown in Figure 8B(c), the mounting table 21 may be raised or lowered to the position of the rack 62 where the next transported item P2 to be dispensed is stored.

[0087] Next, in step S713, the suction control unit 77 stops the suction pump 54 and then opens the relief valve 57. As a result, the suction pressure of the top pad 52B is released to atmospheric pressure (pressure release), and the suction of the top surface Pt of the transported item P1 by the top pad 52B is released. Then, in step S714, the arm 14 is raised, and then, as shown in Figure 8B(d), in step S715, the arm 14 is retracted and moved backward. At this time, the control device 70 may transport the transported item P2 stored in the rack 62 to the mounting table 21.

[0088] Through this series of steps, the transported item P1 can be placed on the installation surface C1 without being dragged. This avoids snagging or misalignment caused by friction between the bottom surface of the transported item P1 and the installation surface C1. As a result, the transport system 1, upon reaching the transport destination, can accurately and smoothly place the transported item P1 on the installation surface C1. Furthermore, before dispensing the transported item P1, the height of the mounting surface of the mounting platform 21 can be brought closer to the height H4 of the installation surface C1 of the transported item P1, and the mounting platform 21 can be advanced to an oblique angle above the mounting surface, allowing for smooth and rapid dispensing of the transported item P2 with only a small range of motion.

[0089] As described above, according to this embodiment, the arm 14 can be extended by sliding the head arm 14A and the intermediate arm 14B horizontally relative to each other using the arm extension mechanism 42A. This allows the picking device 4 to move while minimizing the space required for its operation, and to pull in the transported items P1 to P3 at the transport starting point and dispense the transported items P1, etc. at the transport destination point. Even if a bending moment acts on the arm 14 due to the weight of the suction head 51 when the arm 14 is extended, the bending moment can be absorbed by the pair of arms 14, 14, and the deflection of each arm 14 can be suppressed. As a result, displacement of the suction head 51 can be suppressed.

[0090] Although embodiments of the present invention have been described in detail above, the present invention is not limited to the embodiments described above, and various design modifications can be made without departing from the spirit of the invention as described in the claims.

[0091] In this embodiment, the control device controlled the movement of the suction mechanism's pads, the suction of the pads, and the mounting platform. However, for example, these functions could be operated manually by an operator without using a control device. [Explanation of Symbols]

[0092] 1: Conveying system, 14a: Hand arm (arm component), 14b: Intermediate arm (arm component), 2: Cart, 21: Platform, 4: Picking device, 40: Drive mechanism, 41: Arm lifting mechanism, 42A: Arm extension / retraction mechanism, 42B: Arm linear motion mechanism, 43: Platform lifting mechanism, 44: Platform linear motion mechanism, 50: Holding mechanism, 51: Suction head (holding part), 52B: Top surface pad, 70: Control device, P1~P3: Conveyed items, Pb: Side view, Pt: Top view

Claims

1. A trolley that autonomously travels the route from the starting point of transport to the destination point of the transported goods, A transport system for transporting goods, comprising: a picking device attached to the trolley, which pulls in the transported goods at the transport starting point and dispenses the transported goods at the transport destination point, The picking device is A platform on which the transported items are placed, A holding mechanism including an arm provided with a holding portion for holding the transported item, The system comprises an arm lifting mechanism for raising and lowering the arm, and a drive mechanism having an arm linear motion mechanism for moving the arm in the horizontal direction, with the pulling-in and discharging directions of the conveyed items being horizontal. The conveying system is characterized in that the arm has an arm extension / retraction mechanism that extends and retracts in the horizontal direction by connecting a plurality of arm components to each other so as to be slidable along the horizontal direction.

2. The holding part is a suction head to which multiple pads are attached that adsorb the conveyed item by the suction of air. The transport system according to claim 1, characterized in that the arms are provided in a pair, sandwiching the suction head.

3. The conveying system according to claim 2, characterized in that the suction head is fitted with a side pad for sucking the side of the conveyed item and a top pad for sucking the top surface of the conveyed item.

4. The transport system according to claim 1, wherein the drive mechanism further comprises a platform lifting mechanism for raising and lowering the platform described above.

5. The transport system according to claim 4, wherein the drive mechanism further comprises a linear motion mechanism for moving the aforementioned platform in the horizontal direction relative to the platform lifting mechanism.

6. The transport system further includes a control device that controls the suction of the pad by the suction head, the movement of the arm by the drive mechanism, and the extension and retraction of the arm by the arm extension / retraction mechanism. The control device is At the aforementioned transport starting point, the arm linear motion mechanism and the arm extension / retraction mechanism are controlled to move the arm and extend it until the top surface pad is facing the top surface of the transported item. The arm lifting mechanism and the suction head are controlled so that the top surface pad adheres to the top surface of the transported item. With the top surface pad attached to the top surface, the arm lifting mechanism is controlled to lift the transported item. The transport system according to claim 3, characterized in that the arm linear motion mechanism and the arm extension / retraction mechanism are controlled to move the arm and retract the arm until the transported item is positioned above the mounting surface of the stand described above.

Images