Conveyor device and automatic guided vehicle system

Abstract

A conveyor device (11) comprises: a first conveyor (11A) which has a plurality of rollers (16) arranged in parallel in the conveyance direction of a case (CS), and which conveys the case (CS) on each roller (16) by rotating each roller (16); and a guide frame (17) extending in the horizontal direction along one end of each roller (16), and formed higher than the height of the circumferential surface of each roller (16). As viewed in the vertical direction, each roller (16) is disposed obliquely by making an angle α, which is formed by a shaft (16A) of each roller (16) with respect to the guide frame (17), acute on the downstream side in the conveyance direction of the case (CS).

Description

Conveyor device and automated guided vehicle system

[0001] The present invention relates to a conveyor device for transporting articles and an automated guided vehicle system using the conveyor device, and more particularly to a technique for stabilizing the trajectory of articles transported by the conveyor device.

[0002] Generally, as a conveyor for transporting goods, a roller conveyor is known which has a plurality of rollers arranged in a line in the direction of transport of goods and which rotates each roller to transport goods on each roller. For example, in a generalized warehouse control system described in Patent Document 1, a roller conveyor transports goods, and a robot arm picks up and ships the goods on the roller conveyor.

[0003] Also, various systems have been proposed that move articles using automatic guided vehicles (AGVs). For example, in the automatic guided vehicle system described in Patent Document 2, a package is transported by a conveyor, and when the package arrives at the end of the conveyor, a nearby automatic guided vehicle is called, and a robot loads the package onto the automatic guided vehicle, which then moves the package to a shelf and stores it on the shelf.

[0004] Japanese Patent No. 6887041 Japanese Patent Application Laid-Open No. 2020-123196

[0005] However, when using the technology disclosed in Patent Document 2, in which luggage is transported by a conveyor and then loaded onto an unmanned transport vehicle by a robot after the luggage arrives at the end of the conveyor, the time from when the conveyor starts transporting the luggage to when the luggage is loaded onto the unmanned transport vehicle becomes long, and the luggage is not moved efficiently.

[0006] Furthermore, as a robot for loading luggage onto an automated guided vehicle, it is envisioned to apply an arm robot or the like described in Patent Document 1. However, when such a robot is applied, the system configuration becomes complicated and the system cost increases.

[0007] The inventors of the present invention have devised a new system for efficiently transporting articles by transferring articles from a conveyor to an automated guided vehicle while the automated guided vehicle travels along the conveyor. In this system, in order to transfer the articles from the conveyor to the automated guided vehicle, it is necessary to keep the conveying direction of the articles constant and stable.

[0008] The present invention has been made in consideration of the above circumstances, and has an object to make the direction of transport of articles constant and stable by a conveyor having a plurality of rollers arranged in parallel in the direction of transport of the articles.

[0009] A conveyor device according to one aspect of the present invention comprises: a conveyor having a plurality of rollers arranged in a line in the direction of article transport, which rotates each roller to transport articles on each roller; a guide frame extending horizontally along one end of each roller, formed at a height higher than the peripheral surface of each roller, and supporting one end of each roller; and a support frame extending horizontally along the other end of each roller, formed at a height lower than the peripheral surface of each roller, and supporting the other end of each roller; when viewed from above in the vertical direction, the angle formed by the axis of each roller relative to the guide frame, which is the angle on the downstream side in the direction of article transport, is a predetermined acute angle, and each roller is arranged obliquely relative to the guide frame.

[0010] Another aspect of the present invention provides an automated guided vehicle system comprising the above-described conveyor device and an automated guided vehicle that travels along the side edge of the conveyor that faces the support frame, and the automated guided vehicle is equipped with an imaging unit that captures an image of a mark printed on the surface of an article facing the automated guided vehicle when the article is being transported by the conveyor.

[0011] According to the present invention, the conveyance direction of an article by a conveyor having a plurality of rollers arranged in parallel in the conveyance direction of the article can be made constant and stable.

[0012] 1 is a plan view schematically showing an automated guided vehicle system to which a conveyor device according to an embodiment of the present invention is applied; FIG. 2 is a plan view showing a first conveyor as viewed from a vertical direction; FIG. 3 is a side view showing the first conveyor as viewed from a longitudinal direction of the first conveyor; FIG. 4 is a side view showing a case transported by the first conveyor; FIG. 5 is a plan view schematically showing the first conveyor, a case, and an automated guided vehicle; FIG. 6 is a perspective view schematically showing an automated guided vehicle; FIG. 7 is a perspective view showing a sliding state of each arm of the automated guided vehicle; FIG. 8 is a diagram showing a rack gear and a pinion gear for reciprocating the arm; FIG. 9 is a perspective view showing a mechanism for extending and retracting the first claw portion and the second claw portion of each arm; FIG. 10 is a block diagram showing a control system for the automated guided vehicle; FIG. 11 is a flowchart showing a control procedure for an article movement process; FIG. 12 is a perspective view showing a state in which a case is being transported by the first conveyor; 1 is a perspective view showing a state in which one arm of an automated guided vehicle is in contact with a case being transported by the first conveyor. FIG. 2 is a perspective view showing a state in which a case being transported by the first conveyor is sandwiched between the arms of the automated guided vehicle. FIG. 3 is a perspective view showing the process of transferring a case being transported by the first conveyor to an automated guided vehicle. FIG. 4 is a perspective view showing a state in which a case being transported by the first conveyor is sandwiched between the arms, with first claw portions on the inside of the tip end of each arm protruding. FIG. 5 is a perspective view showing an automated guided vehicle carrying a case that has been transferred from the first conveyor. FIG. 6 is a perspective view showing a state in which an automated guided vehicle is stopped in front of a storage shelf. FIG. 7 is a perspective view showing a state in which a case is sandwiched between the arms of the automated guided vehicle, with second claw portions on the inside of the rear end of each arm protruding. FIG. 8 is a perspective view showing the process of transferring a case from an automated guided vehicle to a storage shelf. FIG. 9 is a perspective view showing an automated guided vehicle after transferring a case to a storage shelf.

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0014] 1 is a schematic diagram showing an automated guided vehicle system Sy to which a conveyor device 11 according to one embodiment of the present invention is applied. The automated guided vehicle system Sy includes an automated guided vehicle 10 and a conveyor device 11 that carries and transports articles. The automated guided vehicle system Sy is installed indoors, such as in a warehouse, that includes storage shelves 12.

[0015] The automated guided vehicle 10 travels by itself along a travel line 15 laid on the floor surface. For example, the travel line 15 is a magnetic tape attached to the floor surface. The automated guided vehicle 10 is equipped with a magnetic sensor that detects the magnetic tape. In the automated guided vehicle 10, a control unit 74 (described later) detects the position of the magnetic tape (travel line 15) based on information obtained from the magnetic sensor, and performs steering control according to the position of the travel line 15 to cause the automated guided vehicle 10 to travel along the travel line 15.

[0016] Alternatively, the travel line 15 may be colored tape attached to the floor, the color or reflectivity of which is different from that of the floor surface. The AGV 10 is equipped with an optical sensor such as a CCD that detects the colored tape. In the AGV 10, a control unit 74 (described later) detects the position of the colored tape (travel line 15) based on information obtained from the optical sensor, and performs steering control according to the position of the travel line 15 to cause the AGV 10 to travel along the travel line 15.

[0017] Both the magnetic tape and magnetic sensor system and the color tape and optical sensor system are known technologies.

[0018] The conveyor device 11 includes a first conveyor 11A and a second conveyor 11B connected to one end of the first conveyor 11A. Both the first conveyor 11A and the second conveyor 11B include a plurality of rollers 16 arranged in parallel along the conveying direction of the cases CS (an example of an article).

[0019] Each roller 16 is supported on the frame of the first conveyor 11A or the second conveyor 11B by its own axis perpendicular to the transport direction of the cases CS. Each roller 16 is driven to rotate in one direction to transport the cases CS on each roller 16. The second conveyor 11B transports the cases CS to one end of the first conveyor 11A, and the first conveyor 11A continues to transport the cases CS.

[0020] The travel lines 15 include a first travel line 15A, a second travel line 15B, a third travel line 15C, and a fourth travel line 15D, which are connected to form a rectangle. Each of the travel lines 15A to 15D is linear. The first travel line 15A extends parallel to the direction in which the first conveyor 11A extends (the direction in which the cases CS are transported). The fourth travel line 15C passes near the storage shelf 12.

[0021] The automated guided vehicle 10 starts traveling from a standby position HP located near the start of the first traveling line 15A, and travels along the first traveling line 15A parallel to the first conveyor 11A. The automated guided vehicle 10 turns its traveling direction by 90 degrees at the end of the first traveling line 15A and starts traveling along the second traveling line 15B. The automated guided vehicle 10 turns its traveling direction by 90 degrees at the end of the second traveling line 15B and starts traveling along the third traveling line 15C. The automated guided vehicle 10 travels along the third traveling line 15C to reach the storage shelf 12, and then turns its traveling direction by 90 degrees at the end of the third traveling line 15C and starts traveling along the fourth traveling line 15D. The automated guided vehicle 10 changes direction by 90 degrees at the end of the fourth traveling line 15D, starts traveling along the first traveling line 15A, and returns to the standby position HP near the start of the first traveling line 15A.

[0022] The unmanned transport vehicle 10 travels parallel to the first conveyor 11A along the first travel line 15A, and as will be described in detail later, transfers the case CS being transported by the first conveyor 11A to the unmanned transport vehicle 10, thereby moving the case CS.

[0023] Fig. 2A is a plan view showing the first conveyor 11A as viewed vertically, and Fig. 2B is a side view showing the first conveyor 11A as viewed in the longitudinal direction (horizontal direction) of the first conveyor 11A.

[0024] As shown in Figures 2A and 2B and Figures 10A and 10B (described later), the first conveyor 11A includes a guide frame 17 and a support frame 18 that extend vertically relative to the ground and form the frame of the first conveyor 11A. The guide frame 17 and the support frame 18 support a plurality of rollers 16. The guide frame 17 and the support frame 18 extend horizontally. The guide frame 17 and the support frame 18 are arranged parallel to each other with a fixed interval between them. A plurality of rollers 16 are arranged side by side between the guide frame 17 and the support frame 18.

[0025] One end of the shaft 16A of each roller 16 is journaled by a guide frame 17, and the other end is journaled by a support frame 18. When the shaft 16A of each roller 16 is rotationally driven by a driving force supplied from a driving source such as a motor, each roller 16 rotates in one direction. This rotation transports the cases CS on each roller 16 in one direction.

[0026] As shown in Figure 2A, when the first conveyor 11A is viewed from above (vertically), the angle α of the shaft 16A of each roller 16 relative to the guide frame 17 extending horizontally, which is the angle downstream in the conveying direction of the cases CS, is set to a predetermined value. The angle α is an acute angle smaller than a right angle, for example, between 85 degrees and 88 degrees. Each roller 16 is disposed at an angle relative to the guide frame 17.

[0027] As shown in FIG. 2B , when the first conveyor 11A is viewed from the horizontal side, each roller 16 is supported by the guide frame 17 and the support frame 18 with one end of the shaft 16A of each roller 16 higher on the guide frame 17 side and the other end of the shaft 16A of each roller 16 lower on the support frame 18 side. Each roller 16 is inclined at a predetermined angle β with respect to the horizontal. The angle β is, for example, between 1 degree and 10 degrees. As such, the angle β is preferably between 1 degree and 10 degrees. It is also possible to set the angle β to 0 degrees, so that each roller 16 is supported by the guide frame 17 and the support frame 18 in a horizontal position relative to the ground.

[0028] The guide frame 17 is formed to a height that protrudes higher than the circumferential surfaces of the rollers 16. The support frame 18 is formed to a height that is lower than the circumferential surfaces of the rollers 16. In other words, no members that protrude higher than the circumferential surfaces of the rollers 16 are provided on the support frame 18 side.

[0029] As described above, the shaft 16A of each roller 16 is inclined at an acute angle α, which is smaller than a right angle, with respect to the guide frame 17 on the downstream side in the conveying direction of the cases CS. As a result, the conveying direction K of the cases CS sent out by each roller 16 is slightly deviated from a direction parallel to the guide frame 17 and faces the guide frame 17.

[0030] Therefore, the case CS is transported on each roller 16 in a direction inclined toward the guide frame 17 from a direction parallel to the guide frame 17. As a result, the case CS is transported while sliding against the guide frame 17, which protrudes higher than the circumferential surface of each roller 16.

[0031] As a result, when multiple cases CS are sequentially transported to one end of the first conveyor 11A by the second conveyor 11B, even if the position of each case CS on the first conveyor 11A varies in the width direction of the first conveyor 11A, the case CS slides against the guide frame 17 while being transported by the first conveyor 11A, and the position of each case CS in the width direction of the first conveyor 11A is maintained constant. In other words, the transport trajectory of the case CS by the first conveyor 11A is constant and stable.

[0032] Furthermore, one end of the shaft 16A of each roller 16 is higher on the guide frame 17 side, and the other end of the shaft 16A is lower on the support frame 18 side, so that each roller 16 is inclined at an angle β with respect to the horizontal, and the support frame 18 is lower than the peripheral surface of each roller 16. As a result, it is possible to quickly move the case CS on each roller 16 toward the other end of each roller 16, which is lower. Furthermore, the case CS can be easily pulled out from above each roller 16 to the outside of the support frame 18.

[0033] If the angle α formed by the axis 16A of each roller 16 relative to the guide frame 17 is set too small, the urging force of the case CS approaching the guide frame 17 will be too large. As a result, the case CS will encounter resistance from the guide frame 17, making it difficult for the case CS to be transported smoothly along the guide frame 17. Therefore, the angle α must be set appropriately. The appropriate angle α must be determined experimentally, taking into consideration the transport speed of the case CS by each roller 16, the frictional force between the guide frame 17 and the case CS, etc. From this perspective, the angle α is set, for example, to be between 85 degrees and 88 degrees.

[0034] Furthermore, if the angle β formed by each roller 16 with respect to the horizontal direction is too large, the case CS will slip down against the biasing force of the case CS as it approaches the guide frame 17. Therefore, the angle β needs to be set appropriately in accordance with the angle α. From this perspective, the angle β is set, for example, between 1 degree and 10 degrees.

[0035] As described above, the first conveyor 11A transports the case CS while sliding against the guide frame 17. As a result, the position of the case CS is maintained constant in the width direction of the first conveyor 11A, stabilizing the transport trajectory of the case CS. Furthermore, each roller 16 is inclined downward toward the support frame 18, and the support frame 18 is lower than the circumferential surface of each roller 16. As a result, the case CS can be easily pulled out from above each roller 16 to the outside of the support frame 18.

[0036] Next, the case CS will be described. As shown in Fig. 3A, a two-dimensional code Q is printed on the side of the case CS. As shown in Fig. 3B, an imaging camera 71 equipped with a CCD or the like is provided on the automated guided vehicle 10. The imaging camera 71 captures an image of the two-dimensional code Q on the side of the case CS being transported by the first conveyor 11A.

[0037] When the first conveyor 11A transports the case CS, the position of the case CS is maintained constant in the width direction of the first conveyor 11A. As a result, the distance between the imaging camera 71 and the two-dimensional code Q on the side of the case CS does not fluctuate, and the imaging camera 71 can accurately capture an image of the two-dimensional code Q on the side of the case CS.

[0038] Furthermore, the case CS can be easily pulled out from above the rollers 16 to the outside of the support frame 18. As a result, the case CS can be easily transferred from the first conveyor 11A to the automatic guided vehicle 10.

[0039] Fig. 4 is an enlarged perspective view showing a schematic view of the automated guided vehicle 10. As shown in Fig. 4, the automated guided vehicle 10 includes a running unit 22 provided on the underside of the vehicle body, and a working unit 23 provided on the upper side of the vehicle body.

[0040] Casters 31 are provided at the four corners of the bottom of the running part 22. A plurality of drive wheels 32 are provided at a distance from each other on the inside of the bottom of the running part 22. Each drive wheel 32 is rotated by a corresponding travel drive motor 33, and as the automated guided vehicle 10 moves, the wheels of each caster 31 are rotated accordingly. The travel drive motors 33 that rotate the drive wheels 32 are controlled for each drive wheel 32, adjusting the rotation speed of each drive wheel 32. This adjustment allows the automated guided vehicle 10 to change its traveling direction.

[0041] The working unit 23 includes a pair of support walls 41 that protrude from and face each other on the upper surface of the working unit 23. Each support wall 41 supports an arm 42 at its upper portion and outer side wall. Each arm 42 is, for example, in the form of a hollow housing. Each arm 42 is supported on each support wall 41 via slide rails 43 so as to be slidable along the support wall 41. The distance between the arms 42 is set to a predetermined distance that is slightly longer than the width of the case CS transported by the conveyor device 11. The arms 42 can insert and clamp the case CS between them.

[0042] 5 is a perspective view showing the sliding state of each arm 42. Each arm 42 is slidably supported on each support wall 41 by two slide rails 43 extending horizontally. Each arm 42 is guided in its movement direction by the slide rails 43 and can move back and forth in the longitudinal direction of each arm 42. Each slide rail 43 has, for example, a configuration known as a three-stage pull-out. Each slide rail 43 has a configuration in which a portion thereof protrudes outward, toward the side of the working unit 23, and can move.

[0043] The slide rails 43 have a first rail provided on the side wall of the support wall 41, and a second rail that is engaged with and supported by the first rail and whose movement direction is guided by the first rail to move to the outside, to the side of the working unit 23. The second rail is attached to the arm 42. This allows each arm 42 to move back and forth in the horizontal direction, allowing the entire arm 42 to protrude outward from the automatic guided vehicle 10 and to be retracted into the automatic guided vehicle 10 from the protruding position.

[0044] As shown in Figure 6, a rack gear 44 is provided at the lower end of each arm 42. Each support wall 41 is provided with a respective arm drive motor 45 (shown in Figure 8). A respective pinion gear 46 is fixed to the output shaft of each arm drive motor 45. When each arm drive motor 45 rotates back and forth, each pinion gear 46 rotates back and forth, and each rack gear 44 and each arm 42 moves back and forth while being guided in the movement direction by the slide rail 43.

[0045] The outward movement of the arm 42 is limited to a position where the arm 42 is not released from the engagement and support by the support wall 41 and the slide rail 43, as shown in Figure 5, by the engagement of the first rail and the second rail of the slide rail 43 and the rotation control of the arm drive motor 45.

[0046] 4 and 5 , a slit 42A is formed in the side surface on the inside of the tip end of each arm 42 (the side facing the other opposing arm 42). Each slit 42A is provided with a first claw 51 that protrudes into the space between the arms 42. A slit 42B is formed in the side surface on the inside of the rear end (base end) of each arm 42 (the side facing the other opposing arm 42). Each slit 42B is provided with a second claw 52 that protrudes into the space between the arms 42.

[0047] As shown in Figures 7A and 7B, each first claw 51 is supported by a rotary shaft 53 inside the hollow, housing-like arm 42. Each second claw 52 is supported by a rotary shaft 54 ​​inside the hollow, housing-like arm 42. Each first claw 51 is rotated back and forth by a claw drive motor 55 (shown in Figure 8) connected to each rotary shaft 53, and performs an action of protruding from the slit 42A into the space between the arms 42 and moving from the space to retract into the arm 42. Each second claw 52 is rotated back and forth by a claw drive motor 56 (shown in Figure 8) connected to each rotary shaft 54, and performs an action of protruding from the slit 42B into the space between the arms 42 and moving from the space to retract into the arm 42.

[0048] 4 and 5 , an imaging camera 71 is provided above the working unit 23. The imaging camera 71 is oriented so as to face the space above the first conveyor 11A when the automated guided vehicle 10 travels along the first traveling line 15A parallel to the first conveyor 11A. In this embodiment, the imaging camera 71 is disposed on the base end side of each arm 42, in the center of the area between the two support walls 41 on the working unit 23 in the traveling direction of the automated guided vehicle 10.

[0049] The imaging camera 71 captures an image of a two-dimensional code (e.g., a QR code (registered trademark)) Q or a mark attached to a case CS being transported on the first conveyor 11A. The imaging camera 71 may be located on the base end side of each arm 42, in the traveling direction of the automated guided vehicle 10, outside one of the support walls 41 on the working unit 23 (outside the area sandwiched between the two support walls 41), or on an upper part of one of the support walls 41, on the side wall facing the other support wall 41. The imaging camera 71 may also be located at a position other than the base end side of each arm 42, as long as it is a position where it can capture an image of the two-dimensional code Q or a mark attached to a case CS being transported on the first conveyor 11A.

[0050] Fig. 8 is a block diagram showing a control system of the automated guided vehicle 10. As shown in Fig. 8, the automated guided vehicle 10 includes travel drive motors 33, arm drive motors 45, claw drive motors 55, claw drive motors 56, an imaging camera 71, a travel line sensor 72, a communication unit 73, and a control unit 74.

[0051] Each travel drive motor 33 rotates and drives each drive wheel 32 of the travel unit 22. Each arm drive motor 45 horizontally moves each arm 42 of the working unit 23. Each claw drive motor 55 causes each first claw 51 to protrude from the slits 42A on the inside of both ends of each arm 42 into the space between the arms 42 and to retract into the arm 42.

[0052] Each claw drive motor 56 causes each second claw 52 to protrude from the slits 42B on the inside of both ends of each arm 42 into the space between the arms 42 and to retract into the arm 42. The imaging camera 71 captures an image of the two-dimensional code Q attached to the case CS on the first conveyor 11A. The travel line sensor 72 detects the travel line 15.

[0053] The communication unit 73 is a communication interface equipped with a communication module such as a LAN chip. The communication unit 73 is connected to the terminal device 81 via a wired or wireless LAN, and transmits and receives data to and from the terminal device 81. The terminal device 81 is, for example, a PC (personal computer), and is operated by a user.

[0054] The control unit 74 includes a processor, a random access memory (RAM), a read-only memory (ROM), and a dedicated hardware circuit. The processor is, for example, a central processing unit (CPU), an application specific integrated circuit (ASIC), or a micro processing unit (MPU). The control unit 74 performs overall control of the automated guided vehicle 10 by the operation of the processor in accordance with a control program stored in the ROM.

[0055] The control unit 74 drives and controls each arm drive motor 45 to reciprocate each arm 42. The control unit 74 drives and controls each claw drive motor 55, 56 to protrude each claw 51, 52 from the respective slits 42A, 42B formed at both ends of each arm 42 or retract into the arm 42. The control unit 74 also acquires an image captured by the imaging camera 71, analyzes the image, and identifies the two-dimensional code Q included in the image.

[0056] Under the control of the control unit 74, the automated guided vehicle 10 stops and waits at the standby position HP, and when the first conveyor 11A starts transporting a case CS, it travels along the first traveling line 15A parallel to the first conveyor 11A while driving each arm 42 to transfer the case CS being transported by the first conveyor 11A to the automated guided vehicle 10. Under the control of the control unit 74, the automated guided vehicle 10 travels in the order of the first traveling line 15A, the second traveling line 15B, and the third traveling line 15C, and moves to and stops in front of the storage shelf 12. Under the control of the control unit 74, the automated guided vehicle 10 transfers the case CS to the storage shelf 12, and travels in the order of the third traveling line 15C, the fourth traveling line 15D, and the first traveling line 15A, and returns to the standby position HP.

[0057] Next, the control procedure for the article movement process for transferring the case CS being transported by the first conveyor 11A to the automatic guided vehicle 10 and moving the case CS by the automatic guided vehicle 10 will be described in detail with reference to the flowchart shown in Figure 9. Note that in Figures 10A, 10B, 12A, and 12B, the guide frame 17 and the support frame 18 are only shown in Figure 10A, and are omitted from Figures 10B, 12A, and 12B.

[0058] As shown in Fig. 1, while the automated guided vehicle 10 is waiting at a standby position HP on the first travel line 15A, the second conveyor 11B begins transporting a case CS. The standby position HP is located at the end of the second conveyor 11B, on the side of the position where it connects to the first conveyor 11A (the starting point of the first conveyor 11A). The case CS on the second conveyor 11B is transported with the attached two-dimensional code Q facing the standby position HP. After the case CS has been transported to the position indicated by the dashed line in Fig. 1, the first conveyor 11A switches its transport direction to the direction of the arrow shown in Fig. 1 and continues transporting the case.

[0059] The automated guided vehicle 10, which is at the standby position HP, captures an image of the two-dimensional code Q on the case CS with the imaging camera 71 when the case CS is transported to the position indicated by the dashed line in Figure 1. The imaging camera 71 of the automated guided vehicle 10, which is at the standby position HP, is located opposite the two-dimensional code Q on the side of the case CS. The two-dimensional code Q contains identification information that indicates an ID unique to the case CS. In the automated guided vehicle 10, the control unit 74 analyzes the two-dimensional code Q captured by the imaging camera 71 and determines whether the ID indicated by the identification information included in the two-dimensional code Q is the same as the ID indicated by identification information previously received from the terminal device 81 via the communication unit 73.

[0060] When the control unit 74 determines that the above conditions are the same, it starts the automatic guided vehicle 10 traveling in the direction of the arrow shown in Figure 1 (step S101). At this point, the first conveyor 11A has started transporting the case CS without changing the position of the case CS. Therefore, the case CS has already passed the position shown by the dashed line in Figure 1, i.e., the standby position HP.

[0061] The control unit 74 detects the position of the traveling line 15 based on the detection output of the traveling line sensor 72, and drives and controls the traveling drive motors 33 of each drive wheel 32 according to the detected position of the traveling line 15, so that the unmanned guided vehicle 10 travels along the first traveling line 15A, parallel to the first conveyor 11A, and in a position close to the first conveyor 11A, with the extension direction of each arm 42 (the longitudinal direction of the arm 42) perpendicular to the traveling line 15, as shown in Figure 10A.

[0062] At this time, the control unit 74 sets the travel speed V of the automated guided vehicle 10 to a predetermined travel speed VA that is faster than the transport speed VS of the case CS by the first conveyor 11A (step S102). The control unit 74 controls the drive of one of the two arm drive motors 45 to protrude one arm 42 located upstream in the transport direction of the case CS into the space above the first conveyor 11A, as shown in FIG. 10B (step S103).

[0063] At this time, the control unit 74 sets the travel speed V of the automatic guided vehicle 10 to the travel speed VA, which is faster than the transport speed VS of the case CS by the first conveyor 11A. As a result, as shown in Figures 10B and 11, one of the arms 42 located upstream in the transport direction of the case CS and protruding into the space above the first conveyor 11A catches up with and comes into contact with the case CS.

[0064] Furthermore, while being transported by the first conveyor 11A, the case CS slides against the guide frame 17. As a result, the position of the case CS in the width direction of the first conveyor 11A is maintained constant, and the transport trajectory of the case CS is stabilized.

[0065] A predetermined mark (for example, a hole formed in the side surface or a predetermined image printed on the side surface, or a two-dimensional code Q) is provided on the side surface of the case CS facing the automatic guided vehicle 10. The imaging camera 71 is provided in a position where it can capture an image of the side surface of the case CS when the one arm 42 catches up with and comes into contact with the case CS.

[0066] The imaging camera 71 captures an image of the mark when the one arm 42 catches up with and comes into contact with the case CS. Furthermore, as described above, the position of the case CS in the width direction of the first conveyor 11A is maintained constant, stabilizing the transport trajectory of the case CS. As a result, the distance between the imaging camera 71 and the two-dimensional code Q on the side of the case CS does not fluctuate, and the imaging camera 71 accurately captures the two-dimensional code Q.

[0067] The control unit 74 acquires the image captured by the imaging camera 71, analyzes the image, and identifies an image showing the mark in the image (step S104). The control unit 74 determines that the one arm 42 has caught up with and is in contact with the case CS, and controls the drive of the arm drive motor 45 for driving the other arm 42 to protrude the other arm 42, which is located downstream in the conveying direction of the case CS, into the space above the first conveyor 11A, as shown in FIG. 12A (step S105).

[0068] The distance between the arms 42 is set to a distance equivalent to the width of the case CS, which is slightly longer than the width of the case CS. Therefore, when the other arm 42 extends, the case CS is sandwiched between the arms 42. Furthermore, when the arms 42 extend under the control of the control unit 74, the distal end of each arm 42 extends to a position beyond the rear end of the case CS in a direction perpendicular to the conveyance direction of the case CS. The control unit 74 extends each arm 42 until the distal end of each arm 42 extends to a position beyond the rear end of the case CS ( FIGS. 12A and 13 ).

[0069] Next, the control unit 74 controls the driving of each claw drive motor 55 to project the first claw 51 on the inner side of the tip of each arm 42 as shown in FIGS. 12B and 13 (step S106).

[0070] The two-dimensional code Q identified in step S104 includes weight information indicating the weight of the items contained in the case CS. The weight information may indicate the weight itself, or, for example, the weight of each item and the number of items contained. The control unit 74 determines the weight of the items based on the weight information and calculates the weight of the items by adding the known weight of the case CS to the weight of the items (step S107). Note that the weight information may also indicate the weight of the items themselves, calculated by adding the known weight of the case CS to the weight of the items contained. In this case, the control unit 74 obtains the weight of the items directly from the weight information.

[0071] At the time of processing in step S170, the control unit 74 is controlling the drive of the travel drive motors 33 of each drive wheel 32 to cause the automatic guided vehicle 10 to travel at the travel speed VA set in step S102. The control unit 74 compares the weight of the item calculated in step S107 with a preset threshold. If the control unit 74 determines that the weight of the item is less than the preset threshold, it maintains the travel speed V of the automatic guided vehicle 10 at the travel speed VA.

[0072] On the other hand, if the weight of the item is equal to or greater than the threshold value, the control unit 74 reduces the traveling speed V of the automatic guided vehicle 10 to a predetermined traveling speed VD that is equal to or greater than the transport speed VS of the case CS by the first conveyor 11A and is slower than the traveling speed VA set in step S102 (step S108). As a result, if the weight of the item contained in the case CS is equal to or greater than the threshold value and is heavy, the traveling speed V of the automatic guided vehicle 10 is reduced while being maintained at or greater than the transport speed VS of the case CS.

[0073] Therefore, when the unmanned transport vehicle 10 is moving while pushing the case CS with the protruding arm 42, the load on each travel drive motor 33 can be reduced, and further, the load from the case CS applied to the one arm 42 can also be reduced, allowing the unmanned transport vehicle 10 to move stably.

[0074] The control unit 74 sets the rotation speed of each arm drive motor 45 according to the weight of the item calculated in step S107 (step S109). For example, the control unit 74 sets the rotation speed of each arm drive motor 45 slower as the weight of the item increases. For example, the control unit 74 stores in advance in its built-in ROM a data table indicating the weight of the item and the rotation speed of each arm drive motor 45 corresponding to that weight for each item. The control unit 74 reads from the data table the rotation speed of each arm drive motor 45 corresponding to the weight of the item calculated in step S107, and sets the read rotation speed as the rotation speed of each arm drive motor 45 corresponding to the weight of the item calculated in step S107.

[0075] The control unit 74 controls the drive of each arm drive motor 45 to rotate each arm drive motor 45 at the rotation speed set in step S108, and as shown in Fig. 14, each arm 42 is retracted from the space above the first conveyor 11A and retracted from the protruding position as described above into an area within the working unit 23 of the automatic guided vehicle 10. When each arm 42 is retracted, each first claw 51 catches on the end of the case CS, and each arm 42 retracts the case CS from the first conveyor 11A into the working unit 23 of the automatic guided vehicle 10 (step S110).

[0076] That is, by retracting each arm 42, the case CS moves from its position on the first conveyor 11A onto the working unit 23 of the automatic guided vehicle 10. In this way, the heavier the item, the slower the movement speed of each arm 42 is, and the case CS is transferred at a slower speed from the first conveyor 11A to the working unit 23 of the automatic guided vehicle 10. Therefore, when each arm 42 retracts the case CS into the working unit 2 of the automatic guided vehicle 10, the load on each arm drive motor 45 can be reduced.

[0077] In addition, the movement of the case CS from its position on the first conveyor 11A to the working section 23 of the unmanned transport vehicle 10 is carried out while transport by the first conveyor 11A and the movement of the unmanned transport vehicle 10 continue, but since this movement is carried out at a low speed, the case CS can be moved stably and reliably from its position on the first conveyor 11A to the working section 23 of the unmanned transport vehicle 10.

[0078] In addition, one end of the shaft 16A of each roller 16 is higher on the guide frame 17 side, and the other end of the shaft 16A is lower on the support frame 18 side, so that each roller 16 is inclined. Furthermore, because the support frame 18 is lower than the peripheral surface of each roller 16, the case CS can be easily pulled out by each arm 42 from each roller 16 to the automatic guided vehicle 10 outside the support frame 18.

[0079] After the case CS is pulled from the first conveyor 11A into the working section 23 of the unmanned transport vehicle 10, the control section 74 controls the drive of each claw drive motor 55 to retract each first claw section 51 and store it within the arm 42.

[0080] The control unit 74 detects the position of the driving line 15 based on the detection output of the driving line sensor 72, and drives and controls the driving drive motors 33 of each drive wheel 32 according to the detected position of the driving line 15, causing the unmanned guided vehicle 10 to travel along a route in the order of the first driving line 15A, the second driving line 15B, and the third driving line 15C (step S111).

[0081] When the automated guided vehicle 10 travels to the position of the storage shelf 12, the control unit 74 uses the imaging camera 71 to capture images of two-dimensional codes attached to different positions on the storage shelf 12 along the traveling direction of the automated guided vehicle 10. The control unit 74 analyzes the captured two-dimensional codes to detect location information of the storage shelf 12 contained in the two-dimensional codes. The control unit 74 has previously received, via the communication unit 73, the location information of the storage shelf 12 linked to the ID unique to the case CS.

[0082] When the control unit 74 captures an image of the two-dimensional code including location information that matches the location information of the storage shelf 12 linked to the ID, it stops the automated guided vehicle 10 at the position at that time, as shown in Fig. 15 (step S112). At this time, the automated guided vehicle 10 is in a position where the tip ends of the arms 42 to which the first claws 51 are attached are facing the storage shelf 12 due to the direction changes that occur when the automated guided vehicle 10 changes paths along the first traveling line 15A, the second traveling line 15B, and the third traveling line 15C.

[0083] The control unit 74 controls the drive of each claw drive motor 56 to project the second claw 52 on the inside of the rear end of each arm 42 as shown in Figures 15 and 16 (step S113). At this time, the second claw 52 on the inside of the rear end of each arm 42 is positioned on the end side of the case CS, opposite the storage shelf 12.

[0084] The control unit 74 controls the drive of each arm drive motor 45 to project each arm 42 toward the storage shelf 12, as shown in Figures 17 and 18 (step S114). The amount of projection at this time is set to an amount that allows the second claw 52 on the inside of the rear end of each arm 42 to enter at least to a position above the storage shelf 12. The slide rail 43 is configured so that the second rail is engaged and supported by the first rail, and the movement direction is guided by the first rail, so that the second rail can also move outward toward the storage shelf 12 (the opposite direction from the outward direction toward the first conveyor 11A shown in Figure 5).

[0085] The control unit 74 causes each second claw 52 to hook onto the case CS by causing each arm 42 to protrude toward the storage shelf 12, and each arm 42 and second claw 52 pushes the case CS from above the working unit 23 of the automatic guided vehicle 10 into the storage shelf 12, thereby moving the case CS from above the working unit 23 of the automatic guided vehicle 10 to the storage shelf 12. The control unit 74 drives and controls each claw drive motor 56 to retract each second claw 52 and store it inside the arm 42.

[0086] The control unit 74 detects the position of the travel line 15 based on the detection output of the travel line sensor 72, and drives and controls the travel drive motors 33 of each drive wheel 32 according to the detected position of the travel line 15, causing the automated guided vehicle 10 to travel along a route in the order of the third travel line 15C, the fourth travel line 15D, and the first travel line 15A. The control unit 74 stops the travel drive motors 33 of each drive wheel 32 a certain time after the automated guided vehicle 10 changes its direction of travel 90 degrees between the fourth travel line 15D and the first travel line 15A, and stops the automated guided vehicle 10 at the standby position HP (step S115).

[0087] As described above, in this embodiment, when the first conveyor 11A starts transporting the case CS, the automated guided vehicle 10 travels along the first travel line 15A parallel to the first conveyor 11A, and one of the arms 42 located upstream in the transport direction extends. At this time, the travel speed V of the automated guided vehicle 10 is set to a travel speed VA that is faster than the transport speed VS of the case CS. When one arm 42 moves to the position of the case CS, the other arm 42 located downstream in the transport direction extends, and the case CS is sandwiched between the arms 42.

[0088] In this state, the first claws 51 on the inside of the tip of each arm 42 protrude, and each arm 42 is pulled back to the automatic guided vehicle 10. At this time, each first claw 51 catches on the case CS, and the case CS is pushed from the first conveyor 11A into the working section 23 of the automatic guided vehicle 10 by the arms 42 and the first claws 51, and moves onto the working section 23 of the automatic guided vehicle 10.

[0089] According to this embodiment, while the unmanned guided vehicle 10 is running, the case CS being transported by the first conveyor 11A can be transferred to the unmanned guided vehicle 10, thereby allowing the case CS to be moved efficiently.

[0090] Furthermore, because the case CS slides against the guide frame 17 while being transported by the first conveyor 11A, the position of the case CS in the width direction of the first conveyor 11A is maintained constant, stabilizing the transport trajectory of the case CS. As a result, the distance between the imaging camera 71 and the two-dimensional code Q on the side of the case CS does not fluctuate, and the imaging camera 71 accurately captures the two-dimensional code Q.

[0091] Furthermore, since each roller 16 is inclined and the support frame 18 is lower than the peripheral surface of each roller 16, the case CS can be easily pulled out by each arm 42 from each roller 16 to the unmanned transport vehicle 10 outside the support frame 18.

[0092] <First Modification> In the first modification, the working unit 23 of the automated guided vehicle 10 moves up and down in the vertical direction. For example, a plurality of support pillars are provided to protrude from the travelling unit 22 of the automated guided vehicle 10, and the working unit 23 is supported by each support pillar so as to be freely movable in the vertical direction, and the working unit 23 is moved up and down by a plurality of ball screws, which are a known mechanism. The ball screws include a screw shaft that protrudes from and is rotatably supported by the travelling unit 22, and a nut that is fixed to the working unit 23 and is screwed onto the screw shaft.

[0093] The traveling unit 22 is equipped with a lifting motor that rotates each screw shaft. The control unit 74 causes each lifting motor to rotate each screw shaft in one direction, thereby raising each nut and the working unit 23. The control unit 74 also causes each lifting motor to rotate each screw shaft in the opposite direction, thereby lowering each nut and the working unit 23. According to the first modification, even if the heights of the conveyor device 11 and the storage shelf 12 change, the working unit 23 can be raised and lowered to match the heights of the conveyor device 11 and the storage shelf 12, making it possible to transfer the case CS between the working unit 23 and the conveyor device 11 or the storage shelf 12.

[0094] <Second Modification> In the second modification, the separation distance between the arms 42 is changed. For example, the working unit 23 is provided with a rack gear extending in the orthogonal direction at the lower end of one of the support walls 41, which supports one of the support walls 41 so as to be slidable in a direction perpendicular to the longitudinal direction of the arm 42. Furthermore, the working unit 23 is provided with a pinion gear that meshes with the rack gear and a motor that rotates the pinion gear back and forth.

[0095] Under the control of the control unit 74, the motor rotates the pinion gear back and forth, causing the rack gear to move back and forth. This moves one support wall 41 and arm 42 toward or away from the other support wall 41 and arm 42, changing the separation distance between the arms 42. According to the second modification, even if the width of the case CS changes, it is possible to sandwich the case CS between the arms 42 and transfer the case CS between the work unit 23 and the conveyor device 11 or the storage shelf 12.

[0096] 1 to 19 are merely examples of the present invention, and are not intended to limit the present invention to these configurations and processes. For example, in the above embodiment, the automated guided vehicle 10 takes in the case CS being transported by the conveyor device 11 and stores it in the storage shelf 12, but the present invention is not limited to such an embodiment.

[0097] For example, the control unit 74 may drive and control the travel drive motor 33, the arm drive motor 45, the claw drive motor 55, and the claw drive motor 56 to operate the arm 42, the first claw portion 51, the second claw portion 52, and the imaging camera 71, so that the unmanned guided vehicle 10 takes in a case CS stored on a storage shelf 12 onto the unmanned guided vehicle 10, transports the case CS to the position of the conveyor device 11, and transfers the case CS from the unmanned guided vehicle 10 onto the conveyor device 11.

Claims

1. a conveyor having a plurality of rollers arranged in a direction of conveyance of the articles, the rollers being rotated to convey the articles on the rollers; a guide frame extending horizontally along one end of each of the rollers, formed at a height higher than the peripheral surface of each of the rollers, and pivotally supporting one end of each of the rollers; a support frame extending horizontally along the other end of each of the rollers, formed at a height lower than the peripheral surface of each of the rollers, and pivotally supporting the other end of each of the rollers; When viewed from above in the vertical direction, an angle formed by an axis of each roller with respect to the guide frame on the downstream side in the conveying direction of the article is an acute angle consisting of a predetermined angle, and each roller is disposed obliquely with respect to the guide frame, a conveyor device in which, when viewed from the side in the direction in which the conveyor transports the articles, each of the rollers has an inclination such that one end of the shaft of each of the rollers is higher on the guide frame side and the other end of the shaft of each of the rollers is lower on the support frame side than the guide frame side.

2. 2. The conveyor device according to claim 1, wherein an upper end of the guide frame is formed higher than a peripheral surface of each of the rollers when viewed from the side in a direction in which the articles are transported by the conveyor.

3. 2. The conveyor system of claim 1, wherein each of the rollers is inclined at an angle of 1 to 10 degrees relative to the horizontal.

4. A conveyor having a plurality of rollers arranged in parallel in the conveying direction of the articles, rotating each roller to convey the articles on each roller; a guide frame extending horizontally along one end of each of the rollers, formed at a height higher than the peripheral surface of each of the rollers, and pivotally supporting one end of each of the rollers; a support frame extending horizontally along the other end of each of the rollers, formed at a height lower than the peripheral surface of each of the rollers, and pivotally supporting the other end of each of the rollers; a conveyor device in which, when viewed from above in a vertical direction, an angle formed by an axis of each of the rollers with respect to the guide frame on the downstream side in the conveying direction of the article is a predetermined acute angle, and each of the rollers is disposed obliquely with respect to the guide frame; an automated guided vehicle that travels along the side edge of the conveyor that is on the support frame side, An automated guided vehicle system, wherein the automated guided vehicle is equipped with an imaging unit that captures an image of a mark printed on a surface of the object facing the automated guided vehicle when the object is being transported by the conveyor.

5. The automated guided vehicle is Drive wheels and a travel drive unit that rotates the drive wheels to cause the automatic guided vehicle to travel; a pair of arms that are provided at respective positions on the automated guided vehicle that are downstream and upstream in the direction in which the conveyor conveys the articles when the automated guided vehicle travels along the conveyor, extend in a direction perpendicular to the direction in which the articles are conveyed, face each other at positions spaced apart by a distance corresponding to the width of the articles in the direction in which the articles are conveyed, and move back and forth in the perpendicular direction so as to be able to protrude outward from the automated guided vehicle and be retracted into the automated guided vehicle from the protruding position; an arm driving unit that causes each of the pair of arms to perform the reciprocating movement; a pair of first claws provided at the tip ends of the pair of arms, each of which is configured to be able to protrude from the tip ends into a space between the pair of arms and to retract into the tip ends; a first claw drive unit that causes each of the pair of first claws to perform either the protruding operation or the retracting operation; Controlling the travel drive unit, the arm drive unit, and the first claw drive unit, the automated guided vehicle is caused to travel at a predetermined first travel speed that is faster than a transport speed of the article, and one of the pair of arms that is provided on the upstream side is caused to protrude from the automated guided vehicle above the conveyor; when the one arm moves to a position of the article being transported by the conveyor, the other arm provided on the downstream side is protruded from the automatic guided vehicle above the conveyor; 5. The automated guided vehicle system according to claim 4, further comprising: a control unit that, when the article is present between the pair of arms, causes the pair of first claw portions to protrude from the tip ends of the pair of arms into the space between the pair of arms and retracts the pair of arms from above the conveyor into the automated guided vehicle.

6. the mark is a two-dimensional code including weight information indicating the weight of the item, 5. The automated guided vehicle system according to claim 4, wherein, when the weight of the item indicated by the weight information is equal to or greater than a predetermined threshold, the control unit controls the travel drive unit to reduce the travel speed of the automated guided vehicle to a predetermined second travel speed that is equal to or greater than the conveying speed of the item and is slower than the first travel speed.

7. the mark is a two-dimensional code including weight information indicating the weight of the item, 5. The automated guided vehicle system according to claim 4, wherein the control unit controls the arm drive unit to reduce the movement speed of the pair of arms when retracting the pair of arms from the space above the conveyor into the automated guided vehicle as the weight of the item indicated by the weight information increases.

8. a pair of second claws provided at rear end portions of the pair of arms, each of the second claws being configured to be able to protrude from the rear end portions into a space between the pair of arms and to retract into the rear end portions; a second claw drive unit that causes each of the pair of second claws to perform either the protruding operation or the retracting operation, 5. The automated guided vehicle system according to claim 4, wherein the control unit controls the arm drive unit and the second claw drive unit to cause the pair of second claw units to protrude from rear ends of the pair of arms into a space between the pair of arms, thereby causing the pair of arms to protrude outward from within the automated guided vehicle.