Alignment device and automatic transfer system

Abstract

To position a loading platform mounted on an automatic transport robot at a predetermined target stopping position with high accuracy. [Solution] The alignment device 1 is equipped with a front-rear position detection sensor 3L fixed to one of the left and right sides of the loading platform 2 to detect the front-rear position of the loading platform 2, a front-rear position detection sensor 3R fixed to the other left and right side of the loading platform 2 to detect the front-rear position of the loading platform 2, a front-rear drive mechanism 4L that can drive one of the left and right sides of the loading platform 2 in the front-rear direction, a front-rear drive mechanism 4R that can drive the other left and right side of the loading platform 2 in the front-rear direction, a left-right position detection sensor 5 fixed to the loading platform 2 to detect the left-right position of the loading platform 2, and a left-right drive mechanism 6 that can drive the loading platform 2 in the left-right direction, and is configured to adjust the front-rear position of the loading platform 2 by the front-rear drive mechanisms 4L and 4R based on the detection results of the front-rear position detection sensors 3L and 3R, and adjust the left-right position of the loading platform 2 by the left-right drive mechanism 6 based on the detection results of the left-right position detection sensor 5.

Description

[Technical Field]

[0001] The present invention relates to an alignment device for an automatic transfer robot, which adjusts the position of a platform mounted on an automatic transfer robot that moves automatically under computer control, and to an automatic transfer system using the same. [Background technology]

[0002] In logistics warehouses, factories, and other facilities, the use of automated guided vehicles (AGVs) to transport goods within the facility is increasing. Conventionally, automated guided vehicles (AGVs) have been used as guides for autonomous travel using magnetic tapes or magnetic bars placed on the floor, etc. However, automated guided vehicle systems using AGVs have difficulty avoiding obstacles on the guided route because their movement path is fixed to the guide route.

[0003] In recent years, there has been a growing introduction of automated guided robots (AMRs) that can recognize their own position and move autonomously based on map data within a facility and measurement data from encoders, gyroscopes, etc., or that can detect obstacles using sensors and determine their own avoidance routes (e.g., Patent Documents 1 and 2).

[0004] In a transport system using an automatic transport robot such as an AGV or AMR, the automatic transport robot generally stops automatically when it determines that it has reached a target stopping position defined in the movement control program, and while in this stopped state, a transport loader belonging to the transport system hands over the transported object to the loading platform mounted on the automatic transport robot. Therefore, the position of the loading platform when the transported object is handed over depends on the stopping position of the automatic transport robot, and on the stopping positioning accuracy of the automatic transport robot relative to the target stopping position. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2023-169034 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-138003 Summary of the Invention [Problem to be solved by the invention]

[0006] However, depending on the transported object, there are cases where the positional relationship between the platform mounted on the automated transport robot and the transport loader needs to be positioned with high precision. In such cases, the stopping positioning accuracy of existing automated transport robots mentioned above may not be sufficient to ensure that the platform is positioned accurately relative to the specified target position. In particular, AMRs, unlike AGVs, do not have a route guide, so their stopping positioning accuracy is relatively poor. Currently, the stopping positioning accuracy guaranteed by automated transport robots is generally around 20 mm in each direction, front to back, left to right, relative to the target stopping position, and at most around 5 mm. Placing the platform at the specified target position with higher precision than this is difficult for commonly used automated transport robots (especially AMRs).

[0007] In view of the above background, an object of the present invention is to more accurately position a loading platform mounted on an automatic transport robot at a predetermined target stopping position. [Means for solving the problem]

[0008] In order to achieve the above-mentioned object, the present invention provides an alignment device that is mounted on an automatic transport robot and used to adjust the position of a platform section that receives transported items, and that includes a first front-to-rear position detection sensor fixed to one of the left and right sides of the platform section to detect the front-to-rear position of the platform section, a second front-to-rear position detection sensor fixed to the other of the left and right sides of the platform section to detect the front-to-rear position of the platform section, a first front-to-rear drive mechanism that can drive one of the left and right sides of the platform section in the front-to-rear direction, a second front-to-rear drive mechanism that can drive the other of the left and right sides of the platform section in the front-to-rear direction, a left-to-right position detection sensor fixed to the platform section to detect the left-to-right position of the platform section, and a left-to-right drive mechanism that can drive the platform section in the left-to-right direction, and that adopts the following configuration 1.The alignment device adjusts the front-to-rear position of the platform section by the first and second front-to-rear position detection mechanisms based on the detection results of the first and second front-to-rear position detection sensors, and adjusts the left-to-right position of the platform section by the left-to-right drive mechanism based on the detection results of the left-to-right position detection sensors.

[0009] If the alignment device according to configuration 1 is mounted on an automatic transport robot, after the automatic transport robot automatically stops moving, it becomes possible to know the positional deviation of the platform unit from a predetermined target stopping position based on the detection results of the left and right front-rear position detection sensors and the left and right position detection sensors, and to adjust the position of the platform unit in each of the front-rear and left-right directions using the left and right front-rear drive mechanisms and the left and right drive mechanisms, thereby further aligning the position of the platform unit to the target stopping position. Therefore, it becomes possible to position the platform unit mounted on the automatic transport robot at the predetermined target stopping position with greater accuracy.

[0010] In the above configuration 1, configuration 2 can be adopted in which the positioning accuracy in the front-rear direction of the first and second front-rear drive mechanisms based on the detection results of the front-rear position detection sensor is 2 mm or less, and the positioning accuracy in the left-right direction of the left-right drive mechanism based on the detection results of the left-right position detection sensor is 2 mm or less.

[0011] According to the above configuration 2, it is possible to handle highly accurate positioning of the loading platform, which is difficult to achieve with the autonomous movement control of an AMR.

[0012] In the above configuration 2, configuration 3 can be adopted in which each of the first and second front-rear drive mechanisms has a feed screw extending in the front-rear direction, a nut combined with the feed screw and connected to the loading platform side in a non-rotatable manner, and an electric motor that drives the feed screw, and the left-right drive mechanism has a feed screw extending in the left-right direction, a nut combined with the feed screw and connected to the loading platform side in a non-rotatable manner, and an electric motor that drives the feed screw, and each of the front-rear position detection sensors and the left-right position detection sensors is an optical distance sensor.

[0013] According to the above configuration 3, the positioning accuracy of the first and second longitudinal drive mechanisms in the longitudinal direction can be 1 mm or less, and the positioning accuracy of the lateral drive mechanism in the lateral direction can also be 1 mm or less.

[0014] In the above configuration 3, a configuration 4 can be adopted in which the first and second front-rear drive mechanisms are constructed on a first support, the left-right drive mechanism is constructed on a second support, the nut of the first front-rear drive mechanism is connected to the second support via a first vertical shaft portion extending in the vertical direction, the nut of the second front-rear drive mechanism is connected to the second support via a second vertical shaft portion extending in the vertical direction, when the nut of the second front-rear drive mechanism is in a stopped state, the nut of the first front-rear drive mechanism moves in the front-rear direction, causing the second support to rotate relative to the first support around the second vertical shaft portion, when the nut of the first front-rear drive mechanism is in a stopped state, the nut of the second front-rear drive mechanism moves in the front-rear direction, causing the second support to rotate relative to the first support around the first vertical shaft portion, and when the nut of the left-right drive mechanism moves in the left-right direction, the loading platform portion moves in the left-right direction relative to the second support.

[0015] According to the above configuration 4, the first and second longitudinal drive mechanisms and the lateral drive mechanism are stacked one above the other, thereby making it possible to reduce the installation area required for mounting the alignment device.

[0016] Configuration 5 is adopted, which is an automatic transport system comprising an automatic transport robot, an alignment device described in any one of configurations 2 to 4 above mounted on the automatic transport robot, and a plurality of light reflective markers arranged at required locations so that distance measurements can be performed by the front-rear position detection sensor and the left-right position detection sensor, wherein after the automatic transport robot automatically stops moving, the alignment device controls the first front-rear drive mechanism and the second front-rear drive mechanism, respectively, so that the distance detected by the first front-rear position detection sensor and the distance detected by the second front-rear position detection sensor are set to an equivalent target distance for front-rear control, and after this control, controls the left-right drive mechanism so that the distance detected by the left-right position detection sensor is set to the target distance for left-right control.

[0017] According to the above configuration 5, after the automatic movement of the automatic transport robot stops, the alignment device can align the position of the loading platform to a predetermined target stopping position using the light reflective marker as a reference, thereby eliminating the need for advanced information transmission between the automatic transport robot and the alignment device. [Effects of the Invention]

[0018] As described above, by adopting the above configuration 1 or 5, the present invention makes it possible to position the platform mounted on the automatic transport robot at a predetermined target stopping position with high accuracy. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a plan view of an automatic transfer robot equipped with an alignment device according to an embodiment of the present invention; [Figure 2] Enlarged cross-sectional view of line II-II in Figure 1 [Figure 3] FIG. 2 is an enlarged plan view showing the longitudinal drive mechanism and the first support body in FIG. 1 ; [Figure 4] FIG. 2 is an enlarged plan view showing the left-right drive mechanism and the second support body in FIG. 1 with the loading platform partly cut away. [Figure 5] Left side view of Figure 1 [Figure 6] 2 is a schematic diagram showing, from the road surface side, the start of position adjustment of the loading platform in an example of an automatic transport system using the alignment device and automatic transport robot of FIG. 1. [Figure 7] A schematic diagram showing the first stage of adjusting the position of the loading platform from the road side, following the start stage in Figure 6. [Figure 8] A schematic diagram showing the second stage of adjusting the position of the loading platform from the road side, following the first stage in Figure 7. [Figure 9] A schematic diagram showing the third stage of adjusting the position of the loading platform from the road side, following the second stage in Figure 8. [Figure 10] A schematic diagram showing the completion of the position adjustment of the loading platform from the road side, following the third stage in Figure 9. [Figure 11] A side view showing an example in which the alignment device of Figure 1 is mounted on the forklift part of an automatic transport robot. [Figure 12] Functional block diagram showing the signal transmission system between the alignment device and the automatic transfer robot in Figure 6. DETAILED DESCRIPTION OF THE INVENTION

[0020] An alignment apparatus according to an embodiment of the present invention will now be described with reference to the accompanying drawings.

[0021] The automatic transport robot shown in Figure 1 is an autonomous mobile vehicle AMR. An alignment device 1 according to the embodiment (hereinafter simply referred to as "alignment device 1") is mounted on the top surface of the body of the autonomous mobile vehicle AMR. The alignment device 1 is used to adjust the position of a loading platform 2 that receives the transported item CO. In the illustrated example, the transported item CO is assumed to be an air shaft, which is a winding core, and a movable V-shaped carrier VC that transfers the transported item CO between the alignment device 1 and the body of the autonomous mobile vehicle AMR is mounted thereon.

[0022] The alignment device 1 comprises a loading platform 2, a first front-rear position detection sensor 3L fixed to one of the left and right sides (left side in the illustrated example) of the loading platform 2 for detecting the front-rear position of the loading platform 2, a second front-rear position detection sensor 3R fixed to the other of the left and right sides (right side in the illustrated example) of the loading platform 2 for detecting the front-rear position of the loading platform 2, a first front-rear drive mechanism 4L (see Figures 2 and 3) capable of driving one of the left and right sides of the loading platform 2 in the front-rear direction, a second front-rear drive mechanism 4R (see Figures 1 and 3) capable of driving the other of the left and right sides of the loading platform 2 in the front-rear direction, a left-right position detection sensor 5 (see Figures 1 and 4) fixed to the loading platform 2 for detecting the left-right position of the loading platform 2, and a left-right drive mechanism 6 (see Figures 1 and 4) capable of driving the loading platform 2 in the left and right direction.

[0023] Here, Figure 1 shows a state in which the platform 2 is positioned at the center of its range of movement in the front-rear direction and at the center of its range of movement in the left-right direction. The front-rear direction and left-right direction in this invention correspond to the first and second axial directions of a two-dimensional Cartesian coordinate system used in the control of the alignment device 1, and refer to the directions when the platform is in the aforementioned center position. In the illustrated example, it is assumed that the front-rear, left-right directions of the alignment device 1 (see Figures 1 and 5) coincide with the two-dimensional Cartesian coordinate system of the front-rear, left-right directions used in the travel control of the automatic transport robot, but the two do not need to coincide.

[0024] The platform 2 (see Figures 1 and 2) includes a holder 21 that directly supports the transported object CO and is moved integrally with the holder 21 when the front-rear drive mechanisms 4L and 4R and the left-right drive mechanism 6 are driven. The holder 21 in the illustrated example is V-block-shaped, supporting the transported object CO, which is an air shaft, at two locations on both the front and rear sides. The platform 2 has a pair of front and rear guide groove members 22 extending in the left-right direction, and a support plate 23 connecting these guide groove members 22. The holder 21 rests on the upper surface of the support plate 23. The guide groove member 22 is fixed to the lower surface of the support plate 23. Air cylinders 7L and 7R are attached to the left and right ends of the support plate 23, respectively, for raising and lowering the transported object CO. The structure of the platform 2 can be modified as desired depending on the shape of the transported object CO, the method of transferring the transported object CO to and from a transport loader, etc.

[0025] The front-rear position detection sensors 3R and 3L are fixed to the front guide groove member 22 via stays. The left-right position detection sensor 5 is fixed to one of the left and right sides (the left side in the illustrated example) of the support plate 23 via a stay.

[0026] Each of these sensors 3R, 3L, and 5 uses an optical distance sensor. The front-rear position detection sensors 3R and 3L emit light from a light source inside the sensor toward the front, receive the light reflected by an object to be measured using a light-receiving element, convert the reflected light into a distance, and output the result. The left-right position detection sensor 5 emits light from a light source inside the sensor toward the other side (the right side in the illustrated example), receive the light reflected by an object to be measured using a light-receiving element, convert the reflected light into a distance, and output the result. By using optical distance sensors in each of these sensors 3R, 3L, and 5, it is possible to detect the distance, which is determined by the position of the loading platform 2 relative to the object to be measured, with an error of less than ±1 mm, or even less than 0.5 mm.

[0027] The longitudinal drive mechanisms 4L, 4R (see Figures 1 to 3) are identically structured and spaced apart in the left-right direction. The longitudinal drive mechanisms 4R, 4L are symmetrically arranged with respect to an imaginary plane that passes through the center of the loading platform 2 in the left-right direction and that extends in the front-rear and up-down directions.

[0028] The first longitudinal drive mechanism 4L is constructed on a first support 41. The first support 41 is a stationary part fixed to the body of the AMR. The first longitudinal drive mechanism 4L has an electric motor 42 attached to the first support, a gearbox 43 that reduces the rotation input from the electric motor 42, a feed screw 44 connected to the output shaft of the gearbox 43, and a nut 45 combined with the feed screw 44. The holding torque of the electric motor 42 makes it possible to maintain the longitudinal position of the nut 45 relative to the feed screw 44.

[0029] The screw axis of the feed screw 44 is aligned in the front-rear direction. The nut 45 converts the forward and reverse rotation of the feed screw 44 into a moving force in the front-rear direction and is moved integrally by that moving force. The nut 45 has a slider portion 45a fixed to the second support 46 at its upper side and combined with a front-rear guide rail 47 at its lower side, and a first vertical shaft portion 45b fixed to the slider portion 45a. The front-rear guide rails 47 are fixed in a pair on the left and right sides to the first support 41. The slider portion 45a and the left and right guide rails 47 function as a linear guide that guides the nut 45 in the front-rear direction. The nut 45 and the second support 46 are connected to the second support 46 via the first vertical shaft portion 45b. The first vertical shaft portion 45b fits snugly into a bearing hole formed in the second support body 46, with its upper head portion in contact with the upper surface of the second support body 46 and its lower portion fixed to the slider portion 45a. When the nut 45 moves back and forth, the second support body 46 can move relative to the nut 45 around the first vertical shaft portion 45b.

[0030] The second longitudinal drive mechanism 4R (see FIG. 3) is similar to the first longitudinal drive mechanism 4L, and is connected to the second support body 46 via a second vertical shaft portion 45b.

[0031] The axis of the first vertical shaft portion 45b, the axis of the second vertical shaft portion 45b, and the central position in the front-to-rear direction of the holder 21 of the loading platform portion 2 are arranged on the same imaginary plane along the left-right and up-down directions.

[0032] When the nut 45 of the second (right) longitudinal drive mechanism 4R is stopped, the nut 45 of the first (left) longitudinal drive mechanism 4L moves in the longitudinal direction, causing the second support 46 to rotate about the second (right) vertical shaft 45b relative to the first support 41. Furthermore, when the nut 45 of the first (left) longitudinal drive mechanism 4L is stopped, the nut 45 of the second (right) longitudinal drive mechanism 4R moves in the longitudinal direction, causing the second support 46 to rotate about the first (left) vertical shaft 45b relative to the first support 41. Based on the detection results of the first and second longitudinal position detection sensors 3L, 3R, the first and second longitudinal drive mechanisms 4L, 4R can perform tilt adjustments by displacing one left or right side and the other left or right side of the bed 2 in opposite longitudinal directions. Furthermore, by synchronously driving the nuts 45 of the first and second (left and right) front-rear drive mechanisms 4L, 4R at a constant speed in the front-rear direction, the position of the loading platform 2 in the front-rear direction can be adjusted.

[0033] The left-right drive mechanism 6 shown in FIG. 1 (see FIGS. 2 and 4) is constructed on the second support 46. The left-right drive mechanism 6 has an electric motor 61 attached to the second support 46, a feed screw 62 connected to the output shaft of the electric motor 61, and a nut 63 combined with the feed screw 62. The electric motor 61 is a geared motor including a reduction mechanism. The screw axis of the feed screw 62 is along the left-right direction. The nut 63 converts the forward and reverse rotation of the feed screw 62 into a moving force in the left-right direction, and is moved integrally by this moving force. The nut 63 is fixed at its upper side to the underside of the support plate 23 of the loading platform 2. The holding torque of the electric motor 61 makes it possible to maintain the left-right position of the nut 63 relative to the feed screw 62.

[0034] Left-right guide rails 46b are integrated with the upper surface of the second support body 46. A pair of front and rear left-right guide rails 46b are fixed to the second support body 46. The front and rear guide groove members 22 of the loading platform 2 are combined with the front and rear guide rails 46b. These guide groove members 22 and guide rails 46b function as linear guides that guide the loading platform 2 in the left-right direction. The loading platform 2 moves left-right relative to the second support body 46 as the nut 63 moves left-right. The left-right position of the loading platform 2 can be adjusted by the left-right drive mechanism 6 based on the detection results of the left-right position detection sensor 5.

[0035] 1 can precisely adjust the longitudinal position of the corresponding nut 45 or the lateral position of the nut 63 by turning the corresponding feed screw 44 or 62 through the drive control of the corresponding electric motor 42 or 61, respectively. This allows the longitudinal positioning accuracy of the corresponding nut 45 or the lateral positioning accuracy of the corresponding nut 63 determined by the drive control to an error of less than ±1 mm, or even less than 0.5 mm. Therefore, even when taking into account the distance detection accuracy of the aforementioned sensors 3R, 3L, and 5, the longitudinal positioning accuracy of the longitudinal drive mechanisms 4L and 4R based on the detection results of the longitudinal position detection sensors 3L and 3R can be set to 2 mm or less, or even less than 1 mm, and the lateral positioning accuracy of the lateral drive mechanism 6 based on the detection results of the lateral position detection sensor 5 can be set to 2 mm or less, or even less than 1 mm.

[0036] When an automatic transport system is constructed using an autonomous mobile vehicle AMR as an example of an automatic transport robot and an alignment device 1 mounted thereon, light reflective markers ML and MR are placed near a predetermined target stopping position TP corresponding to the destination of the autonomous mobile vehicle AMR, as shown in Fig. 6. The predetermined target stopping position TP corresponds to the position where the platform 2 will be when the automatic transport robot stops without misalignment at a moving stop position on the road surface that has been pre-registered as the destination in the control unit of the automatic transport robot. The automatic transport system is constructed so that transported objects are handed over between the platform 2 and other devices in the automatic transport system, such as a transport loader (not shown), based on the state in which the platform 2 is positioned without misalignment at the predetermined target stopping position TP.

[0037] In the illustrated example, two light reflective markers ML and MR are positioned on the same plane perpendicular to the road surface and at the same height from the road surface. The distance between the two light reflective markers ML and MR along the road surface (generally the horizontal distance) is set to the same dimension as the left-right distance between the first and second longitudinal position detection sensors 3L and 3R. The height of the two light reflective markers ML and MR from the road surface is set to the same dimension as the height of the first and second longitudinal position detection sensors 3L and 3R from the road surface. The control unit of the alignment device 1 has pre-registered as the longitudinal control target distance and the left-right control target distance the distance between the first longitudinal position detection sensor 3L and the light reflective marker ML, the distance between the second longitudinal position detection sensor 3R and the light reflective marker MR, and the distance between the left-right position detection sensor 5 and the light reflective marker ML when the loading platform 2 is at a predetermined target stop position TP. These two longitudinal control target distances are set to the same value.

[0038] As illustrated in Figure 7, when an autonomous moving vehicle AMR determines that it has reached a predetermined movement stopping position and automatically stops moving, it is not possible to stop at the predetermined movement stopping position without deviation due to limitations in navigation accuracy.

[0039] For example, consider a case where the autonomous mobile vehicle AMR automatically stops moving at the position shown in Fig. 7. In this stopped state, the left-right direction of the platform 2 is tilted by δ with respect to the left-right direction of the platform 2 at the predetermined target stopping position TP, and the left-right position of the platform 2 is also slightly deviated from the left-right position of the platform 2 at the predetermined target stopping position TP.

[0040] When the autonomous mobile vehicle AMR is stopped at the position shown in Figure 7, the alignment device 1 measures the distance between the front-rear position detection sensor 3L and the light reflection marker ML using the front-rear position detection sensor 3L, and measures the distance between the front-rear position detection sensor 3R and the light reflection marker MR using the front-rear position detection sensor 3R.

[0041] Then, the alignment device 1 controls the first longitudinal drive mechanism 4L and the second longitudinal drive mechanism 4R so that the distance (measured value) detected by the first longitudinal position detection sensor 3L and the distance (measured value) detected by the second longitudinal position detection sensor 3R are aligned to the same longitudinal control target distance.

[0042] This control can be performed separately for the left and right. For example, the alignment device 1 keeps the second longitudinal drive mechanism 4R and the left-right drive mechanism 6 stopped, and controls the first longitudinal drive mechanism 4L so as to eliminate the difference between the distance (measured value) detected by the first longitudinal position detection sensor 3L and the longitudinal control target distance. As a result, the loading platform 2 reaches the position shown in FIG. 8. Next, the alignment device 1 keeps the first longitudinal drive mechanism 4L and the left-right drive mechanism 6 stopped, and controls the second longitudinal drive mechanism 4R so as to eliminate the difference between the distance (measured value) detected by the second longitudinal position detection sensor 3R and the longitudinal control target distance.

[0043] This control eliminates the tilt δ described above, and the left-right direction of the loading platform 2 is aligned with high precision to the left-right direction of the loading platform 2 at the predetermined target stopping position TP, as shown in Figure 9, and the front-rear direction position of the loading platform 2 is also aligned with high precision to the front-rear direction position of the loading platform 2 at the predetermined target stopping position TP. Even after this control is completed, a positional deviation remains between the left-right direction position of the loading platform 2 and the left-right direction position of the loading platform 2 at the predetermined target stopping position TP.

[0044] Therefore, after this control is completed, the alignment device 1 keeps the first and second longitudinal drive mechanisms 4L, 4R stopped, and controls the left-right drive mechanism 6 so that the distance (measured value) detected by the left-right position detection sensor 5 matches the left-right control target distance. This control eliminates any deviation in the left-right position of the platform 2 from the predetermined target stop position TP, and the left-right position of the platform 2 is aligned with the left-right position of the platform 2 at the predetermined target stop position TP with high precision, as shown in Figure 10. Thereafter, the alignment device 1 drives the air cylinder 7 shown in Figure 1 to transfer the transported object CO.

[0045] 1 etc. shows an example in which the alignment device 1 is attached to the body of an autonomous mobile vehicle AMR, but when the alignment device 1 is mounted on an autonomous mobile vehicle AMR with a forklift (so-called AGF), it is also possible to mount the alignment device 1 on the fork part F as shown in Fig. 11. Also, although an example in which an autonomous mobile vehicle AMR is used as an automatic transport robot is shown, it is also possible to mount the alignment device 1 on an AGV.

[0046] 7 to 10, the only signal transmission between the control unit of the alignment device 1 (see FIG. 12) and the control unit of the autonomous mobile vehicle AMR is a stop signal (a signal for communicating information that the autonomous mobile vehicle AMR has automatically stopped at the position shown in FIG. 7) sent from the control unit of the autonomous mobile vehicle AMR to the control unit of the alignment device 1. Note that the only signal sent from the control unit of the alignment device 1 to the control unit of the autonomous mobile vehicle AMR is the aforementioned transported object transfer completion signal (a signal for communicating information that the autonomous mobile vehicle AMR is now ready to move to the next destination).

[0047] As described above, this alignment device 1 (see Figures 1 to 4) is mounted on an automatic guided robot (AMR) and is used to adjust the position of the platform 2 that receives the transported item CO, and is equipped with a first front-rear position detection sensor 3L fixed to one of the left and right sides of the platform 2 to detect the front-rear position of the platform 2, a second front-rear position detection sensor 3R fixed to the other left and right side of the platform 2 to detect the front-rear position of the platform 2, a first front-rear drive mechanism 4L that can drive one of the left and right sides of the platform 2 in the front-rear direction, a second front-rear drive mechanism 4R that can drive the other left and right side of the platform 2 in the front-rear direction, a left-right position detection sensor 5 fixed to the platform 2 to detect the left-right position of the platform 2, and a left-right drive mechanism 6 that can drive the platform 2 in the left and right direction. Based on the results, the first and second front-rear drive mechanisms 4L, 4R can adjust the position of the platform 2 in the front-rear direction (see FIGS. 7 to 9), and the left-right drive mechanism 6 can adjust the left-right position of the platform 2 based on the detection result of the left-right position detection sensor 5 (see FIG. 10). Therefore, if the alignment device 1 is mounted on an automatic transfer robot (AMR), after the automatic transfer robot (AMR) automatically stops moving (see FIGS. 7 to 10), the positional deviation of the platform 2 from a predetermined target stop position TP can be determined based on the detection results of the left and right front-rear position detection sensors 3L, 3R and the left-right position detection sensor 5, and the left and right positions of the platform 2 can be adjusted in each of the front-rear and left-right directions using the left and right front-rear drive mechanisms 4L, 4R and the left-right drive mechanism 6 to further align the position of the platform 2 with the target stop position TP. Therefore, the alignment device 1 makes it possible to position the platform 2 mounted on an automatic transfer robot (AMR) more accurately at the predetermined target stop position TP.

[0048] Furthermore, this alignment device 1 (see Figures 2 and 3) has a longitudinal positioning accuracy of 2 mm or less for the first and second longitudinal drive mechanisms 4L and 4R based on the detection results of the longitudinal position detection sensors 3L and 3R, and a lateral positioning accuracy of 2 mm or less for the lateral drive mechanism 6 based on the detection results of the lateral position detection sensor 5, so it can handle high-precision positioning of the loading platform 2, which is difficult to achieve with the autonomous movement control of an AMR.

[0049] In addition, in this alignment device 1, each of the first and second longitudinal drive mechanisms 4L, 4R has a feed screw 44 extending in the longitudinal direction, a nut 45 combined with the feed screw 44 and non-rotatably connected to the loading platform 2 side (in the illustrated example, the second support 46), and an electric motor 42 that drives the feed screw 44, and the left-right drive mechanism 6 (see Figures 2 and 4) has a feed screw 62 extending in the left-right direction, a nut 63 combined with the feed screw 62 and non-rotatably connected to the loading platform 2 side (in the illustrated example, the support plate 23), and an electric motor 61 that drives the feed screw 62, and since each of the longitudinal position detection sensors 3L, 3R (see Figure 1) and the left-right position detection sensor 5 is an optical distance sensor, the longitudinal positioning accuracy of the first and second longitudinal drive mechanisms 4L, 4R can be 1 mm or less, and the left-right positioning accuracy of the left-right drive mechanism 6 can also be 1 mm or less.

[0050] In addition, in this alignment device 1, the first and second longitudinal drive mechanisms 4L, 4R (see FIGS. 2 and 3) are constructed on a first support 41, and the left-right drive mechanism 6 (see FIGS. 2 and 4) is constructed on a second support 46. The nut 45 of the first longitudinal drive mechanism 4L is connected to the second support 46 via a first vertical shaft portion 45b (see FIGS. 2 and 3) extending in the up-down direction, and the nut 45 of the second longitudinal drive mechanism 4R is connected to the second support 46 via a second vertical shaft portion 45b extending in the up-down direction. When the nut 45 of the second longitudinal drive mechanism 4R is in a stopped state, the nut 45 of the first longitudinal drive mechanism 4L moves in the front-rear direction, causing the second support 46 to move in the front-rear direction. ) rotates relative to the first support 41 around the vertical shaft portion 45b of the first longitudinal drive mechanism 4L, and when the nut 45 of the first longitudinal drive mechanism 4L is stopped, the nut 45 of the second longitudinal drive mechanism 4R moves in the longitudinal direction, causing the second support 46 to rotate relative to the first support 41 around the first (left side in the illustrated example) vertical shaft portion 45b, and when the nut 62 of the left-right drive mechanism 6 (see Figures 2 and 4) moves in the left-right direction, the loading platform portion 2 moves in the left-right direction relative to the second support 46.Therefore, by stacking the first and second longitudinal drive mechanisms 4L, 4R and the left-right drive mechanism 6 one above the other, the installation area required to mount the alignment device 1 can be made compact.

[0051] Furthermore, the automatic transfer system according to this embodiment (see FIG. 6) includes an automatic transfer robot (AMR), an alignment device 1 mounted on the automatic transfer robot (AMR), and a plurality of light reflective markers ML and MR arranged at required locations so that distances can be measured by the longitudinal position detection sensors 3L and 3R and the left-right position detection sensor 5. After the automatic transfer robot (AMR) automatically stops moving, the alignment device 1 drives the first longitudinal drive mechanism 4L and the second longitudinal drive mechanism 4R so that the distance detected by the first longitudinal position detection sensor 3L and the distance detected by the second longitudinal position detection sensor 3R are set to the same longitudinal control target distance. R are controlled respectively (see Figures 7 to 9), and after this control, the left / right drive mechanism 6 is controlled so as to align the distance detected by the left / right position detection sensor 5 with the target distance for left / right control (see Figure 10).By this, after the automatic movement of the automatic transport robot (AMR) stops, the alignment device 1 can align the position of the loading platform 2 to the specified target stopping position TP by itself using the light reflective markers ML and MR as references.This makes it possible to position the loading platform 2 mounted on the automatic transport robot (AMR) more accurately at the specified target stopping position TP, and eliminates the need for advanced information transmission between the automatic transport robot (AMR) and the alignment device 1.

[0052] It should be noted that the embodiments and examples disclosed herein should be considered to be illustrative in all respects and not restrictive. Therefore, the scope of the present invention is defined by the claims, and it is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0053] 1 Alignment device 2 Cargo area 3L First front / rear position detection sensor 3R Second front / rear position detection sensor 4L First front and rear drive mechanism 4R Second front and rear drive mechanism 5 Left and right position detection sensor 6 Left and right drive mechanism AMR Autonomous Mobile Vehicle (Automatic Transport Robot) ML, MR light reflective marker

Claims

1. An alignment device that is mounted on an automatic transport robot and used to adjust the position of a platform that receives transported items, a first front-rear position detection sensor fixed to one of the left and right sides of the loading platform for detecting the position of the loading platform in the front-rear direction; a second front-rear position detection sensor fixed to the other of the left and right sides of the loading platform for detecting the front-rear position of the loading platform; a first front-rear drive mechanism capable of driving one of the left and right sides of the loading platform in the front-rear direction; a second front-rear drive mechanism capable of driving the other of the left and right sides of the loading platform in the front-rear direction; a left-right position detection sensor fixed to the loading platform for detecting the left-right position of the loading platform; a left-right drive mechanism capable of driving the loading platform in the left-right direction, adjusting the position of the loading platform in the front-rear direction by the first and second front-rear drive mechanisms based on the detection results of the first and second front-rear position detection sensors; An alignment device that can adjust the left-right position of the loading platform by the left-right drive mechanism based on the detection result of the left-right position detection sensor.

2. An alignment device as described in claim 1, wherein the front-to-back positioning accuracy of the first and second front-to-back drive mechanisms based on the detection results of the front-to-back position detection sensor is 2 mm or less, and the left-to-right positioning accuracy of the left-to-right drive mechanism based on the detection results of the left-to-right position detection sensor is 2 mm or less.

3. each of the first and second longitudinal drive mechanisms includes a feed screw extending in the longitudinal direction, a nut combined with the feed screw and non-rotatably connected to the loading platform, and an electric motor that drives the feed screw; the left-right drive mechanism includes a feed screw extending in the left-right direction, a nut combined with the feed screw and connected to the loading platform side in a non-rotatable manner, and an electric motor that drives the feed screw; 3. The alignment apparatus according to claim 2, wherein each of the longitudinal position detection sensors and the left and right position detection sensors is an optical distance sensor.

4. the first and second longitudinal drive mechanisms are constructed on a first support; the left-right drive mechanism is constructed on a second support; a nut of the first longitudinal drive mechanism is connected to the second support body via a first vertical shaft portion extending in a vertical direction, and a nut of the second longitudinal drive mechanism is connected to the second support body via a second vertical shaft portion extending in a vertical direction, When the nut of the second longitudinal drive mechanism is in a stopped state, the nut of the first longitudinal drive mechanism moves in the longitudinal direction, causing the second support body to rotate relative to the first support body about the second vertical shaft portion, and when the nut of the first longitudinal drive mechanism is in a stopped state, the nut of the second longitudinal drive mechanism moves in the longitudinal direction, causing the second support body to rotate relative to the first support body about the first vertical shaft portion, 4. The alignment device according to claim 3, wherein the loading platform portion is moved in the left-right direction relative to the second support body when a nut of the left-right drive mechanism moves in the left-right direction.

5. Automatic transport robots and an alignment device according to any one of claims 2 to 4, which is mounted on the automatic transfer robot; a plurality of light reflective markers arranged at required locations so that distances can be measured by the front-rear position detection sensor and the left-right position detection sensor; After the automatic transport robot automatically stops moving, the alignment device controls the first front-to-rear drive mechanism and the second front-to-rear drive mechanism so that the distance detected by the first front-to-rear position detection sensor and the distance detected by the second front-to-rear position detection sensor are set to the same target distance for front-to-rear control, and after this control, controls the left-to-right drive mechanism so that the distance detected by the left-to-right position detection sensor is set to the target distance for left-to-right control.

Images