Conveying system

Abstract

The transported goods cannot be reliably pulled into the trolley once it reaches the transport starting point, nor can they be reliably discharged from the trolley once it reaches the transport destination. [Solution] The transport system 1 comprises a trolley 2 and a picking device 3. The picking device 3 comprises a platform 20 on which the transported item P is placed, a suction mechanism 50 having a pad 52 that adheres to the surface of the transported item P by air suction, and an arm 51 that supports the pad 52, and a moving mechanism 40 having an arm lifting mechanism 41 and an arm linear motion mechanism 42. The arm 51 has a contact portion 51f formed thereon which the arm 51 abuts against the side Ps of the transported item P facing the retraction direction and the discharge direction when the pad 52 is adhered to the top surface Pc of the transported item P.

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 a conveyed item is disclosed. In this technology, the conveying system includes a suction part that adsorbs to the side surface of the conveyed item and moves in a first direction, and a drive belt that moves a conveying surface on which the conveyed item is placed. The suction part places the adsorbed conveyed item on the conveying surface by moving in the first direction, and the suction part is fixed to the drive belt so as to move together with the conveying surface.

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, at the conveying start point, with the suction part adsorbed to the side surface of the conveyed item, the conveyed item together with the suction part is drawn into the conveying surface of the drive belt. However, at this time, the conveyed item is dragged with respect to the placement surface on which the conveyed item is placed, and due to the non-uniform frictional force between the conveyed item and the installation surface, the conveyed item may not be smoothly moved.

[0005] On the other hand, at the conveying destination point, with the suction part adsorbed to the side surface of the conveyed item, the conveyed item together with the suction part is pushed out from the conveying surface of the drive belt. However, even in this case, the conveyed item is slid while being pushed out with respect to the installation surface on which the conveyed item is installed, and the conveyed item may not be smoothly moved.

[0006] The present invention has been made in view of these points, and aims to provide a transport system that can stably pull transported goods into a trolley when it reaches the transport starting point and stably discharge the transported goods from the trolley when it reaches the transport destination. [Means for solving the problem]

[0007] In view of the above issues, 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, wherein the picking device comprises a suction mechanism having a platform on which the transported goods are placed; a pad that suctions the top surface of the transported goods by air suction; and an arm that supports the pad; and a moving mechanism having an arm lifting mechanism for raising and lowering the arm; and an arm linear motion mechanism for horizontally moving the arm in the pull-in direction and the dispensed direction, wherein the arm is formed with a contact portion that, when the pad is suctioned to the top surface of the transported goods, the arm comes into contact with the side surface of the transported goods facing the pull-in direction and the dispensed direction.

[0008] According to the present invention, at the start of transport, the arm is raised and lowered using an arm lifting mechanism so that the lower surface of the pad is higher than the top surface of the transported item, and the arm is moved horizontally using an arm linear motion mechanism. This allows the contact portion of the arm to come into contact with the side surface of the transported item. Next, with the arm in contact with the side surface of the transported item, the arm lifting mechanism is lowered so that the pad adheres to the top surface of the transported item, and the pad is adhered to the top surface of the transported item by air suction using an adsorption mechanism.

[0009] Next, the arm is moved using the arm lifting mechanism to lift the transported item while the pad is attached to its top surface. This places the transported item in a suspended state, but because the side of the transported item is in contact with the contact point of the arm, there is almost no moment acting on the transported item with the pad as the pivot point, and the posture of the transported item can be stabilized. In this way, by providing a contact point on the arm that contacts the side of the transported item, even if the position of the pad's attachment relative to the top surface of the transported item is slightly off from the equilibrium position, the transported item can be lifted in a stable posture and that posture can be maintained. Using the arm linear motion mechanism, the transported item is moved horizontally to pull the lifted transported item into the mounting surface of the mounting platform, and the transported item can be placed on the mounting platform. In this way, the transported item can be stably pulled into the mounting platform without sliding the transported item onto the placement surface of the trolley that has reached the transport starting point.

[0010] Similarly, at the destination, with the contact portion of the arm in contact with the side of the item being transported on the platform, the suction mechanism is used to suction the pad onto the top surface of the item using air. Next, the arm is moved using the arm lifting mechanism to lift the item with the pad attached to its top surface. As described above, since the item is lifted with the contact portion of the arm in contact with its side, the posture of the suspended item can be stabilized. Next, the arm linear motion mechanism is used to move the pad horizontally to the installation surface of the item so that the lifted item is discharged from the platform, and the arm is lowered using the arm lifting mechanism until the item contacts the installation surface. This allows the item to be smoothly installed on the installation surface without sliding the item. In particular, if the pad is elastically deformable, such as a bellows, the pad is prone to localized elastic deformation and misalignment due to variations in frictional force between the bottom surface of the item and the installation surface. However, according to the present invention, the transported item can be placed on the installation surface without sliding the transported item, so that the transported item can be accurately placed on the installation surface from the trolley that has reached the transport destination.

[0011] Here, the contact portion of the arm is not particularly limited in shape as long as it contacts the side of the conveyed item, but in a more preferred embodiment, the contact portion has a surface shape that contacts along the side of the conveyed item. Since the contact portion can be made to contact along the side of the conveyed item, the contact portion and the conveyed item can be made to contact stably, and thus the posture of the conveyed item in the lifted state (intermediate lifting state) can be stabilized.

[0012] In a more preferred embodiment, the arm is provided with a detection sensor that detects when the contact portion of the arm comes into contact with the side surface of the conveyed item due to the horizontal movement of the arm by the linear motion mechanism of the arm. As a result, the detection sensor detects when the contact portion of the arm comes into contact with the side surface of the conveyed item, so that the contact portion of the arm can come into contact with the side surface of the conveyed item without being excessively pushed against the side surface of the conveyed item.

[0013] Here, 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 being raised or lowered. However, in a more preferred embodiment, the moving mechanism further includes a platform lifting mechanism for raising and lowering the mounting platform described above.

[0014] 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.

[0015] The above-described series of operations may be performed manually by an operator, but more preferably, the system further includes a control device that controls the suction of the pad by the suction mechanism and the movement of the arm by the movement mechanism, wherein the control device controls the arm lifting mechanism and the arm linear motion mechanism so that at the transport start point, the pad faces the top surface of the transported product and the contact portion of the arm contacts the side surface of the transported product, the arm lifting mechanism and the suction mechanism so that the pad is attracted to the top surface of the transported product while the contact portion of the arm is in contact with the side surface of the transported product, the arm lifting mechanism and the suction mechanism so that at the transport destination point, the pad is attracted to the top surface and the transported product is lifted, and the arm linear motion mechanism is controlled to pull the transported product horizontally above the mounting surface of the stand described above.

[0016] According to this embodiment, through a series of controls, at the transport start point and the transport destination point, the contact portion of the arm is brought into contact with the side of the transported item, and with the pad adhering to the top surface of the transported item, the transported item is lifted in a stable position and transported. As a result, the transported item can be placed on the installation surface without sliding the transported item relative to the installation surface, thereby avoiding positional displacement caused by frictional force between the transported item and the installation surface, and enabling the transported item to be accurately placed on the installation surface from the transport system's platform upon reaching the transport destination point.

[0017] Furthermore, in a preferred embodiment, the moving mechanism further comprises a platform lifting mechanism for raising and lowering the platform described above, and the control device further controls the raising and lowering of the platform described above by the platform lifting mechanism, wherein at the transport start point, before the transported item is pulled in, the control device controls the platform lifting mechanism so that the height of the mounting surface of the platform described above is the same as the height of the placement surface of the transported item, and at the transport destination point, before the transported item is unloaded, the control device controls the platform lifting mechanism so that the height of the mounting surface of the platform described above is the same as the installation surface of the transported item.

[0018] According to this aspect, before the conveyed item is drawn in, the height of the placement surface of the placement table is adjusted to the same height as the placement surface of the conveyed item, so that the conveyed item can be drawn in smoothly and quickly. Further, before the conveyed item is discharged, the height of the placement surface of the placement table is adjusted to the same height as the installation surface of the conveyed item, so that the conveyed item can be discharged smoothly and quickly within a small operating range.

Advantages of the Invention

[0019] According to the present invention, the conveyed item can be stably drawn into the cart that has reached the conveyance start point, and the conveyed item can be stably discharged from the cart that has reached the conveyance destination point.

Brief Description of the Drawings

[0020] [Figure 1] It is a schematic perspective view of a conveyance system according to an embodiment of the present invention. [Figure 2] It is a block diagram of the conveyance system shown in FIG. 1. [Figure 3] It is a block diagram of the control device shown in FIG. 2. [Figure 4] It is a control flow diagram of drawing in the conveyed item by the control device shown in FIG. 3. [Figure 5] (a) to (d) are diagrams for explaining the drawing-in operation of the conveyed item. [Figure 6] (a) to (c) are diagrams for explaining the drawing-in operation of the conveyed item following FIG. 5(d). [Figure 7] It is a control flow diagram of discharging the conveyed item by the control device shown in FIG. 3. [Figure 8] (a) to (d) are diagrams for explaining the discharging operation of the conveyed item. [Figure 9] (a) and (b) are diagrams for explaining the discharging operation of the conveyed item following FIG. 8(d).

Modes for Carrying Out the Invention

[0021] The transport system 1 according to an embodiment of the present invention will be described below with reference to Figures 1 to 9.

[0022] 1. About the transport system 1 The transport system 1 according to this embodiment is a system that, at the transport starting point, pulls in (takes in) the transported item P which is placed on a shelf C, pallet D, or the lower shelf surface TA for items (transported goods), transports the taken transported item P, and at the transport destination point, dispenses the transported item P and places it on a frame-shaped shelf C, pallet D, or the lower shelf surface TB for items (transported goods) (see Figures 5, 8, etc.).

[0023] In the following specification, the surface on which the transported item P is placed at the transport placement point is referred to as the placement surface TA, and the surface on which the transported item P is installed at the transport destination point is referred to as the installation surface TB. The placement surface TA and the installation surface TB are planes on which the bottom surface of the transported item P makes contact, and are not limited to continuous planes, but also include intermittent planes, such as the surface of a pallet.

[0024] Furthermore, the transported item P is a rectangular packaging box (for example, a cardboard box) containing parts such as machine parts, but the form of the transported item P is not particularly limited as long as the top surface Pc of the transported item P, which will be described later, can be adsorbed by the pad 52, which will be described later.

[0025] In this embodiment, as shown in Figure 1, the transport system 1 comprises at least a trolley 2 that autonomously travels a route from the transport starting point to the transport destination point of the transported goods P, and a picking device 3 attached to the trolley 2 that pulls in the transported goods P at the transport starting point and dispenses the transported goods P at the transport destination point.

[0026] 2. Regarding trolley 2 The trolley 2 is equipped with a picking device 3 and is a device that transports the transported goods P together with the picking device 3. As shown in Figure 1, for example, the trolley 2 can move not only in the two orthogonal directions LA and LB on the floor surface, but in all directions, 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.

[0027] 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, information such as the transport start point, transport destination point, and transport item information (size, placement, and installation location of the transport item P) is input via a wireless signal from an external management computer. The trolley 2 then sets the optimal travel route from the transport start point to the transport destination point and travels using automatic driving control. By controlling the rotation of the trolley 2, the orientation of the trolley 2 is also controlled to match the placement and installation location of the transport item P.

[0028] 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 P in the vertical direction of the same shelf C without driving the trolley 2, or when rotating the trolley 2 of the transport system 1 to place it on a shelf C in a different direction, the transport start point and the transport destination point coincide.

[0029] 3. Regarding picking device 3 The picking device 3 is mounted on a trolley 2 and includes at least a platform 20 on which the transported items P are placed, a suction mechanism 50 that uses air suction to pick up the transported items P, and a moving mechanism 40 that moves a part of the suction mechanism 50 (a pad 52, described later). Although not shown in Figure 1, the picking device 3 is further equipped with an imaging device 8 that images the transported items P (see Figure 2).

[0030] 3-1. Regarding the mounting platform 20 The mounting platform 20 is a flat plate-shaped member, and its leading edge has a tapered shape. The mounting platform 20 has a flat mounting surface on which the conveyed product P is placed. The mounting platform 20 is cantilevered to the carriage 45d of the platform lifting mechanism 45, which will be described later, and is movable in the vertical direction (Z-axis direction).

[0031] 3-2. About the adsorption mechanism 50 The suction mechanism 50 includes a plurality of (for example, six) pads 52 that adsorb to the surface of the conveyed object P (specifically, the top surface Pc) by air suction, and an arm that supports the pads 52. The pads 52 have a bellows-like, expandable and contractible shape, and the tip surface with an opening is the suction surface. In this embodiment, the pads 52 are bellows-like, but the pads 52 are not limited to this form and may be, for example, sponge-like, as long as stable adsorption is possible by the pads 52. Furthermore, a force sensor 59A is provided on the base end side of the pads 52 as a detection sensor to detect contact of the tip surface of the pads 52 (see, for example, Figure 2). Thus, the force sensor 59A is a sensor that detects the force (or contact pressure) when the pads 52 contact the surface of the conveyed object P, and when the detected force (or pressure) exceeds a preset value, it can be determined that the pads 52 have come into contact with the conveyed object P. The force sensor 59A can be a general sensor that uses, for example, a piezoelectric element or a strain gauge. If it is possible to detect contact with the leading edge surface of the pad 52, the detection sensor may, for example, be a positioning sensor (proximity sensor) that measures the distance between the top surface Pc of the conveyed item P and the suction surface of the pad 52.

[0032] The suction mechanism 50 is a mechanism that uses pads 52 to attract the top surface Pc of the transported item P, which is placed on the mounting table 20, at the transport start point and the transport destination point (see, for example, Figures 6(a) and 7(c) described later). Specifically, in this embodiment, multiple pads 52 (for example, 6 in 3 x 2 rows) are arranged at intervals on the lower surface of the tip side of the arm 51, and each pad 52 is positioned so that the suction direction is vertically downward. The number of pads 52 is not limited as long as the transported item can be attracted by the pads 52 and lifted and moved.

[0033] The arm 51 is supported by the moving mechanism 40 (specifically, the arm linear motion mechanism 43) and has a base end portion 51a extending horizontally (in the X direction, described later), a rising portion 51b rising vertically (in the Z direction, described later) from the base end portion 51a, and a tip portion 51c extending horizontally (in the X direction) from the upper part of the rising portion 51b. The base end portion 51a of the arm 51 is provided with a force sensor 59B, which is a detection sensor that detects when the contact portion 51f of the arm 51 comes into contact with the side surface Ps of the conveyed item P due to the horizontal movement of the arm 51 by the arm linear motion mechanism 43. The force sensor 59B may be the same type of sensor as the force sensor 59A, but for example, the detection sensor may be a positioning sensor (proximity sensor) that measures the distance between the side surface Ps of the conveyed item P and the contact portion 51f of the arm 51.

[0034] The rising portion 51b of the arm 51 has a contact portion 51f that abuts against the side surface Ps of the conveyed item P, which faces the arm 51 in the retraction direction and the discharge direction, when the pad 52 is attached to the top surface Pc of the conveyed item P. The side surface Ps of the conveyed item P is the side facing the trolley 2 and the picking device 3. In this embodiment, the contact portion 51f has a surface shape that abuts along the side surface Ps of the conveyed item P. In this embodiment, since the side surface Ps of the conveyed item P is flat, the surface shape of the contact portion 51f is flat. For example, if the conveyed item P is cylindrical, the side surface Ps is a circumferential surface, and therefore the surface shape of the contact portion 51f is a circumferential surface. The pad 52 is attached to the lower surface of the tip portion 51c of the arm 51, and the contact portion 51f is formed at a position lower than the height of the tip surface of the pad 52.

[0035] The pad 52 is connected to the suction pump 54 via a pressure regulating valve 55 and an on / off valve 56. This allows the air sucked in by the suction pump 54 to selectively generate negative pressure inside the pad 52 when it comes into contact with the conveyed item P, thereby causing the pad 52 to adhere to the top surface Pc of the conveyed item P.

[0036] 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 on-off 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.

[0037] 3-3. Regarding the moving mechanism 40 The moving mechanism 40 is a mechanism that moves the pad 52 and the transported item P, which will be described later, along the X, Y, and Z axes. As shown in Figure 1, the X, Y, and Z axes are mutually orthogonal axes. The X axis is the axis along the direction in which the transported item P is pulled in and discharged relative to 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 item P is raised and lowered. The moving mechanism 40 will be described below with reference to Figures 1 and 2.

[0038] Specifically, the moving mechanism 40 includes an arm lifting mechanism 41 that raises and lowers the arm 51 in the vertical direction (i.e., the Z-axis direction), and an arm linear motion mechanism 42 that moves the arm 51 horizontally in the retraction direction and the extension direction (i.e., the X-axis direction).

[0039] The arm lifting mechanism 41 is a mechanism that raises and lowers the arm 51 in the Z-axis direction by driving the arm lifting motor 41a. The arm lifting mechanism 41 is a linear guide mechanism and is connected to the arm lifting motor 41a and comprises a shaft 41b with screw grooves formed on its circumferential surface, and a pair of guide rails 41c arranged parallel to the shaft 41b. The shaft 41b and the guide rails 41c extend in the Z-axis direction, and the shaft 41b rotates around the Z-axis. These components are mounted in a housing 48. The arm lifting mechanism 41 further comprises a carriage 41d, which is screwed onto the shaft 41b and moves along the guide rails 41c. The arm 51 is indirectly attached to the carriage 41d via an arm linear motion mechanism 42, etc.

[0040] When raising or lowering the arm 51 together with the pad 52, the control signal from the control device 70 drives the arm lifting motor 41a, which rotates the shaft 41b around the Z-axis. This allows the carriage 41d, which is screwed onto the shaft 41b, to move together with the arm 51 in the vertical direction (Z-axis direction) along the guide rail 41c.

[0041] The arm linear motion mechanism 42 is a mechanism that moves the arm 51 horizontally along the X-axis direction by driving the arm linear motion motor 42a. The arm linear motion mechanism 42 is a linear guide mechanism similar to that of the arm lifting mechanism 41. The arm linear motion mechanism 42 includes a shaft 42b and a pair of guide rails 42c that extend along the X-axis direction within a casing 42f. The shaft 42b is connected to the arm linear motion motor 42a via a power transmission belt or the like. The arm linear motion mechanism 42 further includes a carriage 42d, which is screwed onto the shaft 42b and slidably connected to the pair of guide rails 42c. The casing 42f is fixed to the carriage 41d of the arm lifting mechanism 41.

[0042] When moving the arm 51 linearly along the X-axis, the control signal from the control device 70 drives the arm linear motor 42a, causing the shaft 42b to rotate around the X-axis. This allows the carriage 42d, which is screwed onto the shaft 42b, to move together with the arm 51 in the horizontal direction (X-axis direction) along the guide rail 42c.

[0043] The moving mechanism 40 further includes an arm linear motion mechanism 43 for moving the arm 51 in the Y-axis direction, a swivel mechanism 44 for swiveling the arm 51 around the Z-axis, and a platform lifting mechanism 45 for raising and lowering the mounting platform 20. The swivel mechanism 44 is fixed to the carriage 42d and is equipped with a swivel motor 44a that swivels the arm 51 together with the pad 52 around the Z-axis. The arm linear motion mechanism 43 is connected to the output shaft of the swivel motor 44a and is a mechanism that linearly moves the arm 51 together with the pad 52 in the Y-axis direction. The arm linear motion mechanism 43 is a linear guide mechanism similar to the arm linear motion mechanism 42 and is equipped with a shaft 43b, etc., and the arm 51 is fixed to the carriage 43d. In this way, the pad 52 can move in the X-axis, Y-axis, and Z-axis directions, and can also swivel around the Z-axis.

[0044] The platform lifting mechanism 45 is a mechanism that raises and lowers the mounting platform 20 in the Z-axis direction by driving the platform lifting motor 45a. The platform lifting mechanism 45 is a linear guide mechanism located in the housing 48, parallel to the arm lifting mechanism 41 in the Y-axis direction. The platform lifting mechanism 45 includes a shaft 45b extending along the Z-axis direction and a pair of guide rails 45c. The platform lifting mechanism 45 further includes a carriage 45d, which is screwed onto the shaft 45b and slidably connected to the pair of guide rails 45c. The mounting platform 20 is fixed to the carriage 45d of the platform lifting mechanism 45.

[0045] When moving the arm 51 linearly along the X-axis direction together with the pad 52, the control signal from the control device 70 drives the arm linear motor 42a, causing the shaft 42b to rotate around the X-axis. This allows the carriage 42d, which is screwed onto the shaft 42b, to move horizontally (in the X-axis direction) along the guide rail 42c.

[0046] When raising or lowering the mounting platform 20, a control signal from the control device 70 drives the platform lifting motor 45a, rotating the shaft 45b around the Z-axis. This allows the carriage 45d, which is screwed onto the shaft 45b, to move together with the mounting platform 20 in the vertical direction (Z-axis direction) along the guide rail 45c. In this way, the arm lifting mechanism 41 and the platform lifting mechanism 45 allow the arm 51 and the mounting platform 20 to be raised and lowered independently.

[0047] 4. Regarding the control device 70 The control device 70 will be described below with reference to Figures 3 to 9. The control device 70 is a device that controls the movement of the pad 52 and the mounting platform 20 by the moving mechanism 40, and in this embodiment, it also controls the automatic movement of the trolley 2. The control device 70 includes, as hardware, a storage device and a computing device, although these are not shown in the figures. The storage device stores a travel map of the warehouse or factory where the trolley travels, operation programs for operating the moving mechanism 40 and the suction mechanism 50, etc. The computing device calculates the travel route from the travel map and calculates decisions on whether to activate the operation programs, etc.

[0048] Specifically, as shown in Figure 3, the control device 70 includes, as software, a trolley travel control unit 71, a transported item detection unit 72, an arm lifting control unit 73, an arm movement control unit 74, a platform lifting control unit 75, and a suction control unit 76, which will be explained along with the following control flow.

[0049] 4-1. Control flow for the retrieval of transported item P The pulling control by the control device 70 will be explained below with further reference to Figures 1 to 3 and Figures 4 to 6. As shown in Figure 4, in step S401, the trolley 2 of the transport system 1 is controlled to move the trolley 2 to the transport start point where the transported item P is placed (see Figure 5(a)). The transported item P is placed on a pallet D on shelf C at the transport start position. Specifically, as shown in Figure 3, 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 transported item P (specifically, the size of the transported item P, the height H1 of the placement surface, etc.) input from the input device 7, and the position information of the trolley 2, and controls the drive device (not shown) of the trolley 2.

[0050] Next, in step S402, upon receiving a detection signal from the trolley travel control unit 71 indicating that the transport start point has been reached, the transport item detection unit 72 uses the imaging device 8 to detect the position of the transport item P at the transport start point.

[0051] Next, in step S403, as shown in Figure 5(b), the control device 70 raises and lowers the arm 51 and the mounting platform 20 according to the height of the placement surface TA of the transported item P. 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 lower surface (suction surface) of the pad 52 is slightly higher than the top surface Pc of the transported item P, in accordance with the detected height H1 of the placement surface TA of the transported item P. The arm movement control unit 74 also controls the arm linear motor 43a of the arm linear motor 43 so that the Y-axis position of the pad 52 is located in the center of the transported item P when viewed from the X-axis direction. Furthermore, the platform lifting control unit 75 controls the platform lifting motor 45a of the platform lifting mechanism 45 so that the height H2 of the mounting surface 21 of the mounting platform 20 is the same height as the height H1 of the placement surface TA of the transported item P. These motor controls are performed based on detection signals from encoders attached to each of the motors 41a, 43a, and 45a, so that the pad 52 and the mounting base 20 are in the target position.

[0052] Next, in step S404, as shown in Figure 5(c), the arm movement control unit 74 controls the arm linear motor 42a of the arm linear mechanism 42 so that the pad 52 moves (forward) toward the conveyed item P together with the arm 51. Next, the process proceeds to step S405, where the force sensor 59B, as described above, determines whether the contact portion 51f of the arm 51 has come into contact with the side surface Ps of the conveyed item P. If the arm movement control unit 74 determines that the contact portion 51f of the arm 51 has not come into contact with the conveyed item P (No), it returns to step S404 and continues the arm 51's movement (forward) toward the conveyed item P. On the other hand, if the arm movement control unit 74 determines that the contact portion 51f of the arm 51 has come into contact with the side surface Ps of the conveyed item P (Yes), it stops driving the arm linear motor 42a and proceeds to step S406.

[0053] Next, in step S406, as shown in Figure 5(d), the arm lifting control unit 73 controls the arm lifting motor 41a of the arm lifting mechanism 41 so that the pad 52, along with the arm 51, descends toward the top surface Pc of the conveyed item P. Next, the process proceeds to step S407, where the force sensor 59A, as described above, determines whether the pad 52 has made contact with the top surface Pc of the conveyed item P. Here, if the arm lifting control unit 73 determines that the pad 52 has not made contact with the top surface Pc of the conveyed item P (No), it returns to step S406 and continues the movement (descension) of the arm 51 toward the conveyed item P. On the other hand, if the arm movement control unit 74 determines that the pad 52 has made contact with the top surface Pc of the conveyed item P (Yes), it stops driving the arm lifting motor 41a and proceeds to step S408.

[0054] In step S406, when the arm 51 is lowered while the contact portion 51f of the arm 51 is in contact with the side surface Ps of the conveyed item P, the contact portion 51f of the arm 51 slides slightly relative to the side surface Ps of the conveyed item P. Therefore, for example, if the pad 52 is a bellows, the height of the suction surface of the pad 52 will be higher than the height of the top surface Pc of the conveyed item P. When the pad 52 is used for suction, the pad 52, which is not in contact with the top surface Pc of the conveyed item P, will elastically deform due to the suction force, and the pad 52 will adhere to the top surface Pc of the conveyed item P. This allows steps S406 and S407 to be omitted and prevents the contact portion 51f of the arm 51 from sliding slightly relative to the side surface Ps of the conveyed item P.

[0055] Next, in step S408, upon receiving a drive stop signal for the arm lifting motor 41a from the arm lifting control unit 73, the suction control unit 76 starts the suction pump 54. As a result, negative pressure is generated inside the pad 52 with the contact portion 51f of the arm 51 in contact with the side surface Ps of the conveyed item P. The suction control unit 76 transmits control signals to the suction pump 54, on-off valve 56, and relief valve 57 shown in Figure 2, based on at least one signal from the arm lifting control unit 73, the arm movement control unit 74, or the detection signal from the pressure gauge 58, and controls their operation.

[0056] Next, in step S409, the suction control unit 76 determines whether the suction pressure (negative pressure) measured by the pressure gauge 58 has fallen below a predetermined pressure. If the suction control unit 76 determines that the suction pressure has not fallen below the predetermined pressure (No), it returns to step S408 and continues suction by the suction pump 54. If it determines that the suction pressure has fallen below the predetermined pressure (Yes), it proceeds to step S410.

[0057] Next, in step S410, as shown in Figure 6(a), the arm lifting control unit 73 controls the arm lifting mechanism 41 to lift the transported item P while the pad 52 is attached to the top surface Pc of the transported item P. As a result, the transported item P is suspended, but since the side surface Ps of the transported item P is in contact with the contact portion 51f of the arm 51, there is almost no moment acting on the transported item P with the pad 52 as the pivot point, and the posture of the transported item P can be stabilized. In this way, by providing the arm 51 with a contact portion 51f that contacts the side surface Ps of the transported item P, even if the attachment position of the pad 52 with respect to the top surface Pc of the transported item P is slightly off from the equilibrium position, the transported item P can be lifted in a stable posture and that posture can be maintained.

[0058] Next, in step S411, as shown in Figure 6(b), the arm movement control unit 74 moves the pad 52 together with the arm 51 toward the mounting surface 21 of the mounting table 20. Specifically, it controls the arm linear motor 42a of the arm linear motion mechanism 42 so that, when viewed from the vertical direction (Z-axis direction), the bottom surface of the transported item P coincides with the mounting surface 21. Next, as shown in Figure 6(c), the process proceeds to step S412, where the arm lifting control unit 73 controls the arm lifting motor 41a of the arm lifting mechanism 41 so that the transported item P descends toward the mounting surface 21. Next, the process proceeds to step S413, where the force sensor 59A, as described above, determines whether the transported item P has come into contact with the mounting surface 21 of the mounting table 20. If the arm lifting control unit 73 determines that the transported item P has not come into contact with the mounting surface 21 of the mounting table 20 (No), it returns to step S412 and continues to lower the arm 51. Meanwhile, if the arm movement control unit 74 determines that the transported item P has come into contact with the mounting surface 21 of the mounting table 20 (Yes), it stops driving the arm lifting motor 41a and proceeds to step S414. In step S414, the suction control unit 76 stops the suction pump 54 and then opens the relief valve 57. As a result, the suction pressure of the pad 52 is released to atmospheric pressure (pressure is released), and the suction of the top surface Pc of the transported item P by the pad 52 is released.

[0059] 4-2. Regarding the dispensing control flow of transported item P The dispensing control by the control device 70 will be explained below with further reference to Figures 7 to 9, along with Figures 1 to 3. First, as shown in Figure 7, in step S601, the trolley 2 of the transport system 1 is controlled to move the transport system 1 on which the transported item P is placed to the transport destination point. 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 point based on the transport start point, transport destination point, and information on the transported item P (specifically, the size of the transported item P, the height H3 of the installation surface, etc.) input from the input device 7, and controls the drive device (not shown) of the trolley 2.

[0060] Next, in step S602, upon receiving a detection signal from the trolley travel control unit 71 indicating that the transport destination point has been reached, the control device 70 raises and lowers the arm 51 and the mounting platform 20 according to the height of the transported item P and the height of the mounting surface TB, as shown in Figure 8(a). 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 pad 52 (the suction surface) is the same height as the height of the transported item P (height of the top surface Pc) placed on the mounting platform 20. In addition, the platform lifting control unit 75 controls the platform lifting motor 45a of the platform lifting mechanism 45 so that the height H4 of the mounting surface 21 of the mounting platform 20 is the same height H3 as the mounting surface TB of the transported item P. These motor controls are performed based on detection signals from encoders attached to each of the motors 41a and 45a so that the arm 51 and the mounting platform 20 are at the target height in the Z-axis. The arm 51 and the mounting base 20 are moved vertically at the same timing and speed.

[0061] Next, in step S603, the suction control unit 76 controls the on / off valve 56 to open as necessary, and then starts the suction pump 54. This creates negative pressure inside the pad 52 while the pad 52 is in contact with the top surface Pc of the conveyed item P. Next, in step S604, the suction control unit 76 determines whether the suction pressure (negative pressure) measured by the pressure gauge 58 has fallen below a predetermined pressure. If the suction control unit 76 determines that the suction pressure has not fallen below the predetermined pressure (No), it returns to step S603 and continues suction by the suction pump 54. If it determines that the suction pressure has fallen below the predetermined pressure (Yes), it proceeds to step S605.

[0062] Next, in step S605, as shown in Figure 8(b), the arm lifting control unit 73 controls the arm lifting mechanism 41 to lift the transported item P, which is placed on the mounting base 20, with the pad 52 attached to the top surface Pc of the transported item P. 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 P is higher than the height H4 of the mounting surface 21 and the height H3 of the installation surface TB. In this way, the arm lifting control unit 73 raises the pad 52 and puts the transported item P into a suspended state. As described above, since the transported item P is lifted with the contact portion 51f of the arm 51 in contact with the side surface Ps of the transported item P, the posture of the transported item P in the suspended state can be stabilized.

[0063] Next, in step S606, as shown in Figure 8(c), the arm movement control unit 74 controls the arm linear motion mechanism 42 so that the transported item P is dispensed horizontally from the mounting base 20 to above the installation surface TB of the transported item P. The arm movement control unit 74 controls the arm linear motion motor 42a of the arm linear motion mechanism 42 so that the pad 52 moves (forward) toward the transported item P together with the arm 51. In this way, the arm movement control unit 74 moves the pad 52 in the X-axis direction and moves the transported item P, which is suspended in the middle, to above the installation surface TB.

[0064] Before proceeding to step S607, the arm movement control unit 74 adjusts the horizontal position (X-axis and Y-axis) of the pad 52. Specifically, it controls the arm linear motors 42a and 43a of the arm linear motion mechanisms 42 and 43 so that, when viewed from the vertical direction (Z-axis), the bottom surface of the conveyed item P is positioned on the installation surface TB.

[0065] Next, in step S607, as shown in Figure 8(d), the arm movement control unit 74 controls the arm lifting motor 41a of the arm lifting mechanism 41 so that the pad 52 moves (descends) together with the arm 51 toward the installation surface Tb of the conveyed item P. Next, the process proceeds to step S608, where the force sensor 59A described above determines whether the conveyed item P has come into contact with the installation surface TB. If the arm movement control unit 74 determines that the conveyed item P has not come into contact with the installation surface TB (No), it returns to step S607 and continues the movement (descends) of the pad 52 toward the conveyed item P. On the other hand, if the arm movement control unit 74 determines that the conveyed item P has come into contact with the installation surface TB (Yes), it stops driving the arm lifting motor 41a and proceeds to step S609.

[0066] Proceeding to step S609, the suction control unit 76 stops the suction pump 54 and then 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 Pc of the conveyed object P by the pad 52 is released.

[0067] This series of steps allows the transported item P to be placed on the installation surface TB without sliding it, thus avoiding snagging or misalignment caused by friction between the bottom surface of the transported item P and the installation surface TB. This enables the transport system 1, upon reaching the transport destination, to accurately and smoothly place the transported item P on the installation surface TB. The height of the mounting surface 21 of the mounting platform 20 is adjusted before the transported item is retracted and before the transported item P is discharged, allowing for smooth and rapid retraction and discharge of the transported item P. In particular, before the transported item P is retracted, the height H2 of the mounting surface 21 of the mounting platform 20 is adjusted to the same height H1 as the placement surface TA of the transported item P, allowing for smooth and rapid retraction of the transported item P. Furthermore, before the transported item P is discharged, the height H4 of the mounting surface 21 of the mounting platform 20 is adjusted to the same height H3 as the installation surface TB of the transported item P, allowing for smooth and rapid discharge of the transported item P with a small range of motion.

[0068] In this state, the arm movement control unit 74 may terminate its control of the arm 51 and move the trolley 2 backward to separate the pad 52 from the transported item P. However, in this embodiment, the control shown in Figures 9(a) and 9(b) may be further performed. Specifically, as shown in Figure 9(a), in step S610, the arm lifting control unit 73 controls the arm lifting mechanism 41 so that the arm 51 rises to the same height as the height from step S607 to step S609, so as to separate it from the top surface Pc of the transported item P. Subsequently, in step S611, as shown in Figure 8(b), the arm movement control unit 74 controls the arm linear motor 42a of the arm linear mechanism 42 so as to pull the pad 52 horizontally together with the arm 51. In this way, since the pad 52 is moved along the same route as the discharge of the transported item P, mechanical interference with surrounding items can be avoided during movement.

[0069] 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.

[0070] In this embodiment, the control device controlled the movement of the pads of the suction mechanism, the suction of the pads, and the control of the mounting platform. However, for example, these functions could be operated manually by an operator without using a control device. [Explanation of Symbols]

[0071] 1: Conveying system, 2: Trolley, 3: Picking device, 20: Platform, 40: Moving mechanism, 41: Arm lifting mechanism, 42: Arm linear motion mechanism, 45: Platform lifting mechanism, 50: Suction mechanism, 52: Pad, P: Conveyed item, Ps: Side view, Pc: 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 suction mechanism comprising a pad that suctions the top surface of the transported item by air suction, and an arm that supports the pad, The system includes a moving mechanism comprising an arm lifting mechanism for raising and lowering the arm, and an arm linear motion mechanism for horizontally moving the arm in the retraction and discharge directions. The conveying system is characterized in that the arm has a contact portion formed thereon, which contacts the side of the conveyed item facing the retraction direction and the discharge direction, with the pad attached to the top surface of the conveyed item.

2. The conveying system according to claim 1, characterized in that the contact portion has a surface shape that contacts along the side surface of the conveyed product.

3. The conveying system according to claim 1, characterized in that the arm is provided with a detection sensor that detects when the contact portion of the arm comes into contact with the side surface of the conveyed product due to the horizontal movement of the arm by the linear motion mechanism of the arm.

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

5. The transport system further includes a control device that controls the suction of the pad by the suction mechanism and the movement of the arm by the moving mechanism. The control device is At the aforementioned transport starting point, the arm lifting mechanism and the arm linear motion mechanism are controlled so that the pad faces the top surface of the transported item and the contact portion of the arm contacts the side surface of the transported item. The arm lifting mechanism and the suction mechanism are controlled so that the pad adheres to the top surface of the conveyed item while the contact portion of the arm is in contact with the side surface of the conveyed item. At the destination transport point, with the pad attached to the top surface, the arm lifting mechanism is controlled to lift the transported item. The transport system according to claim 1, characterized in that the linear motion arm mechanism is controlled to pull the transported item horizontally to above the mounting surface of the stand described above.

6. The aforementioned moving mechanism further comprises a platform lifting mechanism for raising and lowering the aforementioned platform, The control device further controls the raising and lowering of the aforementioned platform by the platform lifting mechanism, The control device is At the aforementioned transport starting point, before the transported item is pulled in, the platform lifting mechanism is controlled so that the height of the mounting surface of the aforementioned platform becomes the same as the height of the placement surface of the transported item. The transport system according to claim 5, characterized in that, at the transport destination point, before the transported item is dispensed, the platform lifting mechanism is controlled so that the height of the mounting surface of the platform described above becomes the same as the height of the installation surface of the transported item.

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