Conveying equipment

Abstract

To provide a conveying facility capable of effectively protecting a floor surface from abrasion caused by friction with wheels of a conveying vehicle.SOLUTION: The transport facility includes a transport vehicle 2 and a floor surface 31 on which the transport vehicle 2 travels. The transport vehicle 2 transports a transport target object. The transport vehicle 2 includes wheels 222 that roll on the floor surface 31, and an own vehicle position recognition device 23 for recognizing the own vehicle position on the floor surface 31. The transport vehicle 2 is configured to change direction with respect to a preset reference position, based on the result of recognition of its own vehicle position by the vehicle position recognition device 23. The transport vehicle 2 performs a direction change position distribution process of distributing the direction change positions within a set distribution range P in a plurality of direction changes with reference to the same reference position.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a conveying facility provided with a carrier that travels on a floor surface.

Background Art

[0002] A conveying facility provided with a carrier that travels on a floor surface is utilized. The carrier travels along a set travel route to convey a conveyance target. An example of such a conveying facility is disclosed in Patent Document 1 below. In the following description of this background art, the reference numerals and names in Patent Document 1 are cited within parentheses.

[0003] In the conveying facility of Patent Document 1, a carrier (carrier for plate-like articles 1) is configured to travel along a travelable route (travel route 2) within a conveyance area (clean room) and convey a conveyance target (plate-like article) to each of a plurality of stations (3). Since the carrier (carrier for plate-like articles 1) repeatedly travels on the travelable route (travel route 2) on the floor surface (floor portion), there is a possibility of wear due to friction with the wheels (travel wheels 5) of the carrier (carrier for plate-like articles 1). Therefore, in the conveying facility of Patent Document 1, in order to protect the floor surface (floor portion) from wear due to friction with the wheels (travel wheels 5) of the carrier (carrier for plate-like articles 1), the strength of the floor surface (floor portion) is increased.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in order to increase the strength of the floor surface (floor portion), the cost of the members constituting the floor surface (floor portion) tends to increase accordingly, and thus the cost of the conveying facility also tends to increase.

[0006] Therefore, there is a need for a transport system that can effectively protect the floor surface from wear caused by friction with the transport vehicle's wheels. [Means for solving the problem]

[0007] In view of the above, the transport equipment is a transport vehicle that transports an object to be transported, and a floor surface on which the transport vehicle travels, The transport vehicle comprises wheels that roll on the floor surface and a vehicle position recognition device for recognizing its own position on the floor surface. A sheet-like reinforcing member having a surface with higher wear resistance than the floor surface is placed on the floor surface at a position including the position of the wheels of the transport vehicle when it is in a reference position. The transport vehicle, based on the results of the vehicle position recognition device, will perform a preset procedure. The aforementioned It is configured to change direction based on a reference position, and the position where the transport vehicle changes direction is designated as the direction change position. The transport vehicle, in multiple turns of direction based on the same reference position, Within the range in which the wheels of the transport vehicle during the change of direction do not protrude from the surface of the reinforcing member. Execute a direction change position distribution process to distribute the direction change positions within the set distribution range. death, In the direction change position distribution process, the transport vehicle determines the direction change position such that, for multiple direction changes based on the same reference position, the distribution of the number of direction changes at each direction change position with respect to the distance between the reference position and the direction change position follows a normal distribution. .

[0008] This configuration allows the transport vehicle to change direction based on a pre-set reference position, while distributing the turning points across multiple turns based on that reference position. This makes it less likely for specific areas of the floor surface to wear down significantly more than other areas due to friction with the wheels. Therefore, this configuration effectively protects the floor surface from wear caused by friction with the wheels while reducing the need to reinforce the floor surface to avoid wear on specific areas. Furthermore, this configuration allows reinforcing members to be placed in areas of the floor where friction with the wheels is more likely to occur than in other areas. Therefore, areas of the floor that are prone to wear due to friction with the wheels can be properly protected. Moreover, this configuration allows for a relatively small variation in the turning position relative to the reference position during multiple turns using the same reference position, while appropriately distributing the turning positions during multiple turns using the same reference position.

[0009] Further features and advantages of the technology relating to this disclosure will become clearer from the following description of exemplary and non-limiting embodiments, with reference to the drawings. [Brief explanation of the drawing]

[0010] [Figure 1] Schematic diagram of the conveying equipment according to the first embodiment [Figure 2] Side view of the transport vehicle shown in Figure 1. [Figure 3] Front view of the transport vehicle shown in Figure 1. [Figure 4] Figure 1 shows the state of the transport vehicle before it changes direction. [Figure 5] Figure 4 shows the state of the transport vehicle changing direction. [Figure 6] Figure 5 shows the state of the transport vehicle after it has changed direction. [Figure 7] Figure 4 shows the relationship between the number of direction changes and the distance from the reference position to the direction change position within the distribution range. [Figure 8] Diagram showing the distribution range in the conveying equipment of the second embodiment. [Modes for carrying out the invention]

[0011] 1. Overview of the conveying equipment in the first embodiment The conveying equipment 1 according to this embodiment will be described with reference to the drawings. As shown in Figure 1, the conveying equipment 1 is equipment for conveying objects 10 from a conveying source to a conveying destination. The conveying source and destination include, for example, a station for receiving objects 10 into an automated warehouse (not shown) or retrieving objects 10 from an automated warehouse, manufacturing equipment, and a work area. The manufacturing equipment is equipment for manufacturing goods, etc., using objects 10. The work area includes, for example, a shipping work area and a sorting work area. The shipping work area is an area where work is done to ship the objects 10. The sorting work area is a sorting area where sorting work is done on the objects 10.

[0012] Figure 1 illustrates a dispatch station 32 as the source of transport, for retrieving the transported object 10 from a warehouse (not shown) where the transported object 10 is stored. It also illustrates a receiving station 33 as the destination, for receiving the transported object 10 into the warehouse where the transported object 10 is stored.

[0013] The conveying equipment 1 includes a conveying area 3 which is an area where the object to be conveyed 10 is conveyed, a conveying vehicle 2 that conveys the object to be conveyed 10, and a control system (not shown) that controls the conveying vehicle 2. The conveying vehicle 2 travels on the floor surface 31 that constitutes the conveying area 3 to convey the object to be conveyed 10 from the conveying source to the conveying destination. One or more conveying vehicles 2 are traveling within the conveying area 3. Specifically, the floor surface 31 is a floor surface 31 provided inside a building or a floor surface 31 provided within a certain outdoor range, including planar ones. For a conveying vehicle 2 that travels on such a floor surface 31, compared with an overhead conveying vehicle that travels along a rail suspended from the ceiling or a rail-mounted trolley that travels along a track arranged on the floor surface 31, the area where the conveying vehicle 2 can travel is large. Therefore, the effect of efficiently protecting the floor surface 31 is significant.

[0014] Hereinafter, the conveying vehicle 2, the conveying area 3, and the control system will be described. For convenience of explanation, one of the two directions along the floor surface 31 is referred to as the "first direction D1", and the other of the two directions along the floor surface 31 is referred to as the "second direction D2". The direction intersecting the "first direction D1" and the "second direction D2" is referred to as the "vertical direction D3".

[0015] 2. Conveying Area The conveying area 3 includes an unloading facility as the conveying source, a loading facility as the conveying destination, an auxiliary facility (not shown) that assists the traveling of the conveying vehicle 2, a traveling area 34 composed of the floor surface 31 on which the conveying vehicle 2 travels, and a reinforcing member 4. The reinforcing member 4 is a member for reinforcing the floor surface 31 of the traveling area 34. The conveying area 3 illustrated in FIG. 1 shows one floor inside a factory or warehouse building.

[0016] In this embodiment, a travel area 34 is provided at a position adjacent to the loading equipment and the unloading equipment. A transport vehicle 2 travels on the floor surface 31 provided in the travel area 34. Therefore, on the floor surface 31, friction occurs between the floor surface 31 and the wheels 222 (described later) of the transport vehicle 2 at the locations where they come into contact. And due to the friction between the floor surface 31 and the wheels 222, the floor surface 31 may experience wear. The reinforcing member 4 prevents wear from occurring at the locations on the floor surface 31 where contact with the wheels 222 occurs. In the following description, the locus on the floor surface 31 where the wheels 222 of the transport vehicle 2 traveling on the travelable path 23R contact is referred to as the wheel locus WT.

[0017] The reinforcing member 4 is arranged at specific locations on the wheel locus WT where the wear due to the friction between the wheels 222 and the floor surface 31 is greater than other locations. Here, the magnitude of the wear due to the friction between the wheels 222 and the floor surface 31 is determined according to at least one of the magnitude of the frictional force acting on the floor surface 31 and the frequency with which the frictional force acts. Specifically, as the frictional force acting on the floor surface 31 increases, the wear occurring on the floor surface 31 increases. Also, as the frequency with which the frictional force acts on the floor surface 31 increases, the wear occurring on the floor surface 31 increases.

[0018] The specific locations include locations where the number of contacts between the wheels 222 and the floor surface 31 is large and locations where the transport vehicle 2 changes direction. By arranging the reinforcing member 4 at the specific locations, the wheels 222 of the transport vehicle 2 passing through the specific locations come into contact with the reinforcing member 4. As a result, the reinforcing member 4 contacts the wheels 222 instead of the floor surface 31, thereby preventing wear due to the friction between the floor surface 31 and the wheels 222 at the specific locations.

[0019] 3. Transport Vehicle The transport vehicle 2 unloads the object to be transported 10 at the loading location and loads the object to be transported 10 at the unloading location. To perform this function, as shown in FIGS. 2 and 3, the transport vehicle 2 includes a transfer device 21, a traveling device 22, and a self-vehicle position recognition device 23.

[0020] The transfer device 21 supports the object to be transported 10 and is a device for transferring the object to be transported 10 at the source and destination of transport. In this embodiment, the transfer device 21 moves the object to be transported 10 in the vertical direction D3. Specifically, when the transport vehicle 2 is positioned at the outbound station 32, which is an example of a transport source, the transfer device 21 receives the object to be transported 10 located in the warehouse or outbound station 32. On the other hand, when the transport vehicle 2 is positioned at the inbound station 33, which is an example of a transport destination, the transfer device 21 moves the object to be transported 10 located in the warehouse or inbound station 33 to a position where the object to be transported 10 is handed over at the warehouse or inbound station 33.

[0021] The transfer device 21 may include, for example, a lifting mechanism (lifter) for raising and lowering the object to be transported in the vertical direction D3. Alternatively, the transfer device 21 may include a fork-type or conveyor-type transfer mechanism or a pushing mechanism (pusher) for moving the object to be transported in the first direction D1 or the second direction D2. Or, the transfer device 21 may include a mechanism for moving the object to be transported in both the vertical direction D3 and the first direction D1 or the second direction D2, for example, a fork-type transfer machine.

[0022] The running gear 22 is a device for moving the transport vehicle 2. The running gear 22 comprises a chassis 221 and wheels 222 that roll on the floor surface 31. Various devices for transporting the target transported object are mounted on the chassis 221. The wheels 222 are rotatably supported relative to the chassis 221. The wheels 222 illustrated in Figures 1 to 3 are located at the bottom of the chassis 221.

[0023] In this embodiment, the running gear 22 comprises a plurality of wheels 222. The plurality of wheels 222 include drive wheels W1 that are rotationally driven by a drive source such as a motor. The chassis 221 can move as the drive wheels W1 rotate. In addition, in this embodiment, the plurality of wheels 222 include driven wheels W2. The driven wheels W2 are wheels 222 that rotate in accordance with the movement of the chassis 221, which moves in conjunction with the rotation of the drive wheels W1.

[0024] In this embodiment, the multiple wheels 222 include a pair of drive wheels W1 and four driven wheels W2. The pair of drive wheels W1 are positioned at the bottom of the chassis 221, spaced apart in the width direction (second direction D2 in Figure 2). The driven wheels W2 are also positioned at the bottom of the chassis 221, similar to the drive wheels W1. Each of the four driven wheels W2 is positioned at one of the four corners of the chassis 221.

[0025] In this embodiment, the driven wheels W2 are equipped with a direction-changing function that changes the direction of the transport vehicle 2. Each driven wheel W2 changes its posture so as to change the angle of inclination with respect to the first direction D1 in the vertical direction D3 view, with respect to the axis of rotation in the vertical direction D3 view, thereby changing the direction of travel of the transport vehicle 2. Hereafter, for the sake of explanation, the change in the angle of inclination with respect to the first direction D1 in the vertical direction D3 view, in order for the driven wheels W2 to perform their direction-changing function, will be referred to as "the driven wheels W2 changing their posture."

[0026] In this embodiment, as shown in Figures 4 to 6, the transport vehicle 2 sets a turning position based on a reference position, and turns around using the axis passing through the turning position and along the vertical direction D3 as the pivot axis WX. In other words, the pivot axis WX when the transport vehicle 2 turns is determined by the arrangement of the multiple wheels 222 in the vertical direction D3 view. The pivot axis WX illustrated in Figures 4 to 6 is the position where the distance from the driven wheel W2 of the four wheels is equal in the vertical direction D3 view.

[0027] In this embodiment, the transport vehicle 2 changes direction while stopped. When the transport vehicle 2, as illustrated in Figures 2 and 3, changes direction, the four driven wheels W2 of the stationary transport vehicle 2 change their orientation toward the direction to be changed. After the orientation of the four driven wheels W2 is changed, the pair of drive wheels W1 rotate, allowing the transport vehicle 2 to travel toward the direction to be changed.

[0028] The vehicle position recognition device 23 is a device for recognizing the vehicle's position on the floor surface 31. The vehicle includes the transport vehicle 2 to which the vehicle position recognition device 23 is attached, and the transport vehicle 2 whose position is recognized by the control system. The vehicle's position on the floor surface 31 is determined by its coordinates in a coordinate system set based on a reference position provided on the floor surface 31, or by the distance to a wall or equipment located in the transport area 3.

[0029] The transport vehicle 2 is configured to change direction based on a preset reference position, using the vehicle position recognition result from the vehicle position recognition device 23 as a reference. Therefore, the transport vehicle 2 changes direction when it reaches the preset position.

[0030] In this embodiment, as shown in Figure 3, the vehicle position recognition device 23 includes a detection unit 231 which serves as a reference position for setting a traversable path 23R on which the transport vehicle 2 can travel, and a detection unit 232 which detects the detection unit 231. The detection unit 232 is mounted on the chassis 221, and the detection unit 231 is installed in the transport area 3. In this embodiment, the reference position is the position of each of the multiple detection units 231 arranged on the floor surface 31. As shown in Figure 1, the transport vehicle 2 is configured to travel along a path (traversable path 23R) that is set to connect the multiple detection units 231. In the example shown in Figure 1, the detection units 231 are regularly arranged at intervals on the floor surface 31 of the travel area 34.

[0031] In this embodiment, the detected unit 231 includes, for example, a magnetic material, an identification code such as a one-dimensional code or a two-dimensional code. If the detected unit 231 is a magnetic material, the detection unit 232 is composed of a detector or the like that detects the magnetic material. If the detected unit 231 is an identification code, the detection unit 232 is composed of a code reader or the like that reads the identification code. However, the detection unit 232 and the detected unit 231 are not limited to this configuration as long as the detection unit 232 can detect the detected unit 231. For example, the detected unit 231 may be composed of an IC (Integrated Circuit) tag and the detection unit 232 may be composed of an IC tag reader. Alternatively, the detected unit 231 may be composed of a mark that is detected by being imaged by the detection unit 232.

[0032] 4. Control System The control system controls one or more transport vehicles 2. Specifically, the control system moves the transport vehicles 2 to designated locations, including the source and destination, and causes the transport vehicles 2 to perform actions for the transfer of the transported objects 10 at the designated locations. In the example of control of the transport vehicle 2 by the control system shown in Figure 1, the controlled transport vehicle 2 moves from the dispatch station 32 in a first direction D1 and changes direction to travel in a second direction D2. The control system then moves the changed-direction transport vehicle 2 to the receiving station 33. For the sake of explanation, the transported objects 10 transported by the transport vehicle 2 are not shown in Figure 1. Also, for the sake of explanation, hereafter, the control system's control of the transport vehicle 2's movement will be simply referred to as the transport vehicle 2 moving.

[0033] The control system calculates multiple candidate possible travel paths 23R for transport vehicle 2 to move to a designated location. From the calculated multiple possible travel paths 23R, the control system sets the actual travel path 23A on which transport vehicle 2 will travel. Then, the control system drives transport vehicle 2 along travel path 23A to move transport vehicle 2 to the designated location.

[0034] The control system assigns a transport task to each of the multiple transport vehicles 2 for transporting the object to be transported 10. The transport task includes an instruction to transport the object to be transported 10 from the source to the destination. Each transport vehicle 2 to which the transport task has been assigned by the control system transports the object to be transported 10 from the source to the destination according to the transport task. The transport task also includes an instruction for the travel route 23A of the transport vehicle 2 to which the transport task has been assigned. As a result, the transport vehicle 2 travels along a route (travel route 23A) selected from among the pre-set possible travel routes 23R based on the recognition result of its own position by the vehicle position recognition device 23.

[0035] The control system includes, for example, a higher-level control device (not shown) that manages the entire transport equipment 1, and a vehicle control device (not shown) that controls each transport vehicle 2. The higher-level control device and the vehicle control devices are configured to communicate with each other. The higher-level control device assigns transport tasks to the vehicle control devices (transport vehicles 2). The vehicle control device that has been assigned a transport task controls various devices installed on itself according to that transport task. The higher-level control device and the vehicle control devices are equipped with, for example, a processor such as a microcomputer, peripheral circuits such as memory, etc. Each process or function is realized through the cooperation of this hardware and a program executed on a processor such as a computer.

[0036] 5. Operation of the transport vehicle In the following sections, the driving operation of transport vehicle 2 will be explained with reference to Figures 4 to 6.

[0037] As shown in Figure 4, the transport vehicle 2 travels along the traversable path 23R toward a position within the distribution range P set based on the reference position. In practice, the transport vehicle 2 travels along a traversable path 23R that overlaps with the reference path 23A, or a traversal path 23A that deviates slightly from the reference path. Here, the reference path is the ideal path for the transport vehicle 2 set to connect two reference positions. For example, the reference path is set to connect the positions where the two detected units 231 are located in a straight line.

[0038] The distribution range P is the position where the transport vehicle 2 changes direction. In this embodiment, the position where the transport vehicle 2 changes direction is determined based on the pivot axis WX. The transport vehicle 2 changes direction at a position where the pivot axis WX is located within the distribution range P in the vertical direction D3 view. Note that the part that serves as the reference for changing direction in the transport vehicle 2 is not limited to the pivot axis WX of the transport vehicle 2, but can be determined as appropriate according to the structure and application of the transport vehicle 2. For example, the part that serves as the reference for changing direction in the transport vehicle 2 may be the corner or center of the chassis 221 in the vertical direction D3 view. Hereafter, for the sake of explanation, "the part that serves as the reference for changing direction in the transport vehicle 2 is located within the distribution range P in the vertical direction D3 view" will be referred to as "the transport vehicle 2 is located within the distribution range P".

[0039] The distribution range P is set around the reference position. The reference position may be located within the distribution range P or outside of it. The distribution range P is determined by considering factors that affect wear due to friction between the wheels 222 of the transport vehicle 2 and the floor surface 31. For example, the distribution range P is determined by considering the number of times the transport vehicle 2 changes direction, the manner of the direction change, the strength of the floor surface 31, etc. To elaborate, the manner of the direction change is a concept that includes, for example, whether the transport vehicle 2 turns or performs another action, and the angle of the direction change. The distribution range P illustrated in Figure 4 is the range inside a circle centered on the reference position.

[0040] The transport vehicle 2 performs a direction change position distribution process for multiple direction changes based on the same reference position. The direction change position distribution process is a process that distributes the direction change positions within a set distribution range P. The direction change position distribution process may distribute the direction change positions uniformly within the distribution range P, or it may distribute the direction change positions probabilistically within the distribution range P. To elaborate, the direction change position distribution process that uniformly distributes the direction change positions within the distribution range P includes a process in which multiple direction change positions are predetermined within the distribution range P, and the number of times the transport vehicle 2 actually changes direction at each direction change position is approximately the same. On the other hand, the direction change position distribution process that probabilistically distributes the direction change positions within the distribution range P includes a process in which the transport vehicle 2 randomly sets the direction change positions with a certain probability. For example, the transport vehicle 2 may set the direction change positions evenly throughout the entire distribution range P, or it may set the direction change positions so that the number of times they are set in a certain range close to the reference position is relatively high.

[0041] As shown in Figure 4, the transport vehicle 2 travels toward a predetermined reference position. In the example shown in Figure 4, the transport vehicle 2 is traveling toward the first direction D1. Upon reaching a distribution range P set near the predetermined reference position, the transport vehicle 2 changes direction within the distribution range P. In the example shown in Figure 5, the transport vehicle 2 stops briefly at the position where it changes direction (direction change position), and performs a rotational movement with the rotation axis WX as the center of rotation, while the rotation axis WX does not move in the vertical direction D3 view. Due to the rotational movement, the direction of travel of the transport vehicle 2 changes from the first direction D1 to the second direction D2.

[0042] As shown in Figure 6, the transport vehicle 2, having completed its turn at a turning point within the distribution range P, resumes its journey. Since the turning point is slightly off the reference path, the transport vehicle 2, having completed its turn, travels along a travel path 23A that is slightly off the reference path. Travel path 23A merges with the reference path at a position away from the detected unit 231. The transport vehicle 2 illustrated in Figure 6 is traveling along travel path 23A, which merges with the reference path along the second direction D2.

[0043] As described above, with the direction change position distribution process, when the transport vehicle 2 repeatedly changes direction at the same reference position, the position of the wheel trajectory WT shifts each time a direction change is performed, thus effectively protecting the floor surface 31 from friction with the wheels 222. In the following sections, several examples of the direction change position distribution process that can further effectively protect the floor surface 31 will be described. Note that the examples shown below may be applied individually to the direction change position distribution process described above, or they may be applied in combination as long as no contradictions arise.

[0044] [Example 1] As explained above, reinforcing members 4 are placed on the floor surface 31 of the transport area 3, as shown in Figure 1. Wear due to friction between the wheels 222 and the floor surface 31 occurs more significantly at the direction change position than at other positions. Therefore, by placing the reinforcing members 4 at the direction change position, the reinforcing members 4 can effectively protect the floor surface 31. For this reason, as shown in Figure 4, it is preferable that the reinforcing members 4 be placed on the floor surface 31 at a position that includes the position of the wheels 222 of the transport vehicle 2 at the reference position.

[0045] In this example, the distribution range P is set to a range in which the wheels 222 of the transport vehicle 2 during a change of direction do not extend beyond the surface of the reinforcing member 4. In this embodiment, the reinforcing member 4 is positioned on the floor surface 31 at the location where the driven wheels W2 change their orientation when the transport vehicle 2 changes direction. The reinforcing member 4 illustrated in Figure 5 is positioned at the location where the transport vehicle 2, which has stopped to perform a turning operation, changes the orientation of the driven wheels W2. Specifically, in Figure 5, the reinforcing member 4 is positioned at four locations around the reference position. The distribution range P is set so that the position where the driven wheels W2 change their orientation in order for the transport vehicle 2 to perform a turning operation overlaps with the reinforcing member 4 in a vertical direction D3 view. With this configuration, when the transport vehicle 2 changes direction, the driven wheels W2 change their orientation while in contact with the surface of the reinforcing member 4. In addition, when the transport vehicle 2 repeatedly changes direction, the position where the driven wheels W2 change their orientation on the reinforcing member 4 shifts each time a change of direction is performed, so wear caused by friction between the reinforcing member 4 and the wheels 222 can be reduced.

[0046] [Example 2] The processing capacity of the processing system varies depending on the specifications of the conveying equipment 1. Furthermore, if the processing capacity of the processing system is not very high, it may be better to determine the direction change positions within the distribution range P according to a simple rule. This example shows one such rule.

[0047] In this example, the transport vehicle 2 pre-sets a set number of turning positions relative to the same reference position during the direction change position distribution process. Each time the transport vehicle 2 performs a direction change relative to the reference position, it determines the turning position by sequentially adopting the set number of turning positions. Specifically, if the number of settings is N (where N is a natural number), N turning positions relative to the same reference position are set, and the N turning positions are sequentially adopted so that all of the N consecutive turning positions are different.

[0048] Figure 4 illustrates the case where the number of settings is five. In this case, the transport vehicle 2 sets five positions within the distribution range P. In Figure 4, the first position P1, second position P2, third position P3, fourth position P4, and fifth position P5 are set within the distribution range P. The first position P1, second position P2, third position P3, fourth position P4, and fifth position P5 are arranged, for example, clockwise around a reference position. In the example shown in Figure 4, the distances from the reference position to each of the first position P1 to fifth position P5 are different. Each time the transport vehicle 2 enters the distribution range P and changes direction, it stops at the positions listed in the order of first position P1, second position P2, third position P3, fourth position P4, and fifth position P5 and changes direction. In the example shown in Figure 5, the transport vehicle 2 that enters the distribution range P after passing second position P2 is depicted. The transport vehicle 2, illustrated in Figure 5, is changing direction at the third position P3.

[0049] [Example 3] In some cases, it is preferable to relatively increase the number of times the transport vehicle 2 changes direction at a particular location. For example, if the strength of the floor surface 31 varies depending on the location, increasing the number of times the transport vehicle 2 changes direction at locations with relatively higher strength on the floor surface 31 can suppress wear due to friction between the floor surface 31 and the wheels 222.

[0050] In this example, the transport vehicle 2 is configured to determine its turning position according to a specific distribution algorithm. As shown in Figure 8, the distribution algorithm determines the turning position such that, for multiple turning maneuvers based on the same reference position, the distribution of the number of turning maneuvers at each turning position relative to the distance between the reference position and the turning position follows a normal distribution. In the graph shown in Figure 8, the distance from the reference position to the turning position is shown on the horizontal axis, and the number of turning maneuvers at that turning position is shown on the vertical axis. In Figure 8, the turning position that coincides with the reference position is set as the median of the normal distribution. In other words, it is set so that the number of turning maneuvers is highest at the turning position that coincides with the reference position, and the number of turning maneuvers decreases as the position moves further from the reference position.

[0051] In addition, the orientation of the turning position relative to the reference position may be periodically varied for the transport vehicle 2. For example, although not shown in the diagram, the transport vehicle 2 may set turning positions at 36 locations, each with an angle of 10° different from the reference position. The transport vehicle 2 may then change direction at a position that is 10° different each time at the 36 turning positions, completing one rotation in 36 turns.

[0052] 6. Conveying equipment according to the second embodiment The transport equipment 1 of the second embodiment will be described with reference to Figure 8. In the first embodiment, the vehicle's position was determined based on the detected unit 231. However, depending on the application of the transport equipment 1, it may not be possible to install a dedicated detected unit 231 for determining the reference. Therefore, there may be a need for a vehicle position recognition device 23 that can recognize the vehicle's position without installing a detected unit 231.

[0053] The transport equipment 1 of the second embodiment differs from the transport equipment 1 of the first embodiment in that it can recognize its own position even if the transport vehicle 2's vehicle recognition device does not detect the detected unit 231. Hereafter, the differences between the transport equipment 1 of the second embodiment and the transport equipment 1 of the first embodiment will be mainly described, and other points will be omitted from the explanation.

[0054] The vehicle position recognition device 23 includes a detector 233 that detects components 35 of the unloading area arranged around the transport vehicle 2, and a computing device 234. Here, the components 35 of the transport area 3 are, for example, walls that demarcate the transport area 3, or devices installed in the transport area 3. The computing device 234 creates map information based on the detection results of the detector 233. The computing device 234 then identifies the vehicle's position on the map represented by the map information.

[0055] The detector 233 detects whether or not the component 35 is located within a certain range around the vehicle. In this embodiment, the detector 233 is mounted on the chassis 221. Therefore, when the detector 233 mounted on the transport vehicle 2 that transports the vehicle in the travel area 34 detects that the component 35 is located within a certain range around the vehicle, the arithmetic unit 234 obtains the positional relationship between the component 35 and the transport vehicle 2 as the detection result.

[0056] In this embodiment, the arithmetic unit 234 creates map information representing a map of the transport area 3 based on the positional relationship (detection result of the detector 233) between the transport vehicle 2 traveling in the transport area 3 and the components 35. The map information includes a coordinate system set with respect to a specific component 35. The arithmetic unit 234 expresses its own position using the coordinates in the coordinate system included in the map information.

[0057] The transport vehicle 2 travels along a route 23A selected from among a plurality of candidate traversable routes 23R calculated by the control system, similar to the first embodiment. In this embodiment, the traversable routes 23R are determined based on a map represented by map information. For example, the traversable routes 23R are set based on a reference position set relative to the location where the components 35 are located on the map represented by map information.

[0058] Preferably, the detector 233 is a sensor that measures the distance from objects placed around the vehicle to the vehicle's position. With this configuration, the positional relationship between the components 35 and the transport vehicle 2 can be obtained with high accuracy. Therefore, the calculation unit 234 can obtain map information that represents a map with high accuracy in position and distance. As a result, the transport vehicle 2 traveling along the travel path 23A has little deviation from the travel path 23A defined by the control system. The detector 233 illustrated in Figure 8 is a laser rangefinder.

[0059] 7. Other Embodiments Next, other embodiments of the conveying equipment 1 will be described.

[0060] (1) In this embodiment, the running gear 22 is described as having a pair of drive wheels W1. However, the number of drive wheels W1 is not limited to one pair. For example, the running gear 22 may have one or more than one pair of drive wheels W1. Also, in this embodiment, it is described that four driven wheels W2 are located at the bottom of the chassis 221. However, the number of driven wheels W2 may be other than four. Furthermore, the driven wheels W2 may be located elsewhere than at the bottom of the chassis 221.

[0061] (2) In this embodiment, it has been explained that among the multiple wheels 222 provided by the running gear 22, there are drive wheels W1 and driven wheels W2. However, all of the multiple wheels 222 provided by the running gear 22 may be drive wheels W1.

[0062] (3) In this embodiment, the vehicle position recognition device 23 was described as comprising a detection unit 232 and a detected unit 231. However, the vehicle position recognition device 23 can have any configuration as long as it can recognize the vehicle's position on the floor surface 31. For example, the vehicle position recognition device 23 may be a position recognition device that uses radio waves, such as GPS (Global Positioning System). In this case, the vehicle's position on the floor surface 31 is determined by coordinates in a coordinate system set based on a reference position provided on the floor surface 31. With these configurations, there is no need to place a reference for the transport vehicle 2 to travel in the travel area 34, so the entire transport equipment 1 becomes simpler.

[0063] (4) In this embodiment, the driven wheel W2 has been described as having a direction-changing function. However, the drive wheel W1 may have a direction-changing function instead of the driven wheel W2. In addition, both the driven wheel W2 and the drive wheel W1 may have a direction-changing function.

[0064] (5) In this embodiment, the reference path has been described as, for example, a path that connects two different detected parts 231 in a straight line. However, the reference path may also be a path that connects two different detected parts 231 in a curved line, or a path formed by combining a path that connects two different detected parts 231 in a straight line and a path that connects two different detected parts 231 in a curved line.

[0065] (6) In this embodiment, the transport vehicle 2 has been described as performing a turning motion as a change of direction. However, the change of direction performed by the transport vehicle 2 is not limited to a turning motion, as long as it is an action that changes the direction in which the transport vehicle 2 is traveling. For example, the transport vehicle 2 may change direction by gradually changing its course while traveling. To clarify, curved travel refers to a mode of travel in which the transport vehicle 2 changes direction while its center position moves in the vertical D3 view. When the transport vehicle 2 performs curved travel, the change of direction position is the starting position of the change of direction or the center of the arc-shaped travel trajectory of the transport vehicle 2 (center of the arc).

[0066] (7) In this embodiment, the distribution range P has been described as including the range inside a circle centered on a reference position. However, the distribution range P may also be the range inside a circle centered on a position other than a reference position. Furthermore, the boundary line of the distribution range P is not limited to a circle, but may be a polygon or the like, as long as a certain range can be defined. The distribution range P may be set to the same range for all of the multiple reference positions installed on the floor surface 31, or different ranges may be set for each reference position. In addition, the setting of the distribution range P may be configured to be changeable. With this configuration, the distribution position can be changed as appropriate considering the condition of the floor surface 31, thus enabling flexible operation of the transport vehicle 2. For example, even when changing the equipment layout to install new equipment in an already set distribution range P, the transport vehicle 2 can be operated in a way that avoids the new equipment simply by changing the setting of the distribution range P.

[0067] (8) In this embodiment, as an example of a position where the direction changes when a set number is defined, the first position P1 to the fifth position P5, which are arranged clockwise, have been described. However, the multiple direction change positions that are set by defining a set number are not limited to being arranged clockwise around the reference position. For example, the multiple direction change positions may be arranged counterclockwise around the reference position, or they may be arranged randomly within the distribution range P.

[0068] (9) In this embodiment, the variance algorithm used the median of the normal distribution as the reference point. However, the median of the normal distribution may be set at a position far from the reference point.

[0069] (10) The configurations disclosed in each of the embodiments described above can be applied in combination with configurations disclosed in other embodiments, as long as no inconsistencies arise. With regard to other configurations, the embodiments disclosed herein are merely illustrative in all respects. Therefore, various modifications can be made as appropriate without departing from the spirit of this disclosure.

[0070] 8. Summary of this embodiment The following is a summary of the embodiments of the conveying equipment described above.

[0071] The conveying equipment comprises a conveying vehicle for conveying objects and a floor surface on which the conveying vehicle travels, The transport vehicle comprises wheels that roll on the floor surface and a vehicle position recognition device for recognizing its own position on the floor surface. The transport vehicle is configured to change direction based on a preset reference position, using the vehicle position recognition result obtained by the vehicle position recognition device as a reference. The position at which the transport vehicle changes direction is defined as the direction change position. The transport vehicle performs a direction change position distribution process to distribute the direction change positions within a set distribution range during multiple direction changes based on the same reference position.

[0072] This configuration allows the transport vehicle to change direction based on a pre-set reference position, while distributing the turning points across multiple turns based on that reference position. This makes it less likely for specific areas of the floor surface to wear down significantly more than other areas due to friction with the wheels. Therefore, this configuration effectively protects the floor surface from wear caused by friction with the wheels while reducing the need to reinforce the floor surface to avoid wear on specific areas.

[0073] Furthermore, it is preferable that the transport vehicle sets the direction change position based on the reference position and performs the direction change using an axis passing through the direction change position and along the vertical direction as the pivot axis.

[0074] In this configuration, since the transport vehicle rotates around a pivot axis that is aligned vertically at the turning point, wear on the floor surface tends to be greater along the trajectory of the transport vehicle's wheels while it is rotating at that turning point compared to other areas. Therefore, the floor surface protection effect of performing the above-mentioned direction change position distribution process is high.

[0075] Furthermore, the transport equipment has a reference position which is the position of each of the multiple detection units located on the floor surface. The transport vehicle is configured to travel along a path set to connect a plurality of the detected units, Preferably, the vehicle position recognition device is configured to recognize the vehicle's position based on the detection of each of the detected parts.

[0076] This configuration allows for the realization of a transport system that can move a transport vehicle to its desired location with a relatively simple structure. Furthermore, this configuration allows for highly accurate setting of the direction change position based on the position of the detected part. Therefore, if the direction change position distribution process is not performed, wear on the floor surface at the direction change position tends to be greater than at other locations. Conversely, by performing the direction change position distribution process, it becomes easier to appropriately distribute the direction change positions during multiple direction changes based on the same reference position.

[0077] Furthermore, the conveying equipment includes a sheet-like reinforcing member having a surface with higher wear resistance than the floor surface, positioned on the floor including the position of the wheels of the conveying vehicle at the reference position. Preferably, the aforementioned dispersion range is set to a range in which the wheels of the transport vehicle during the change of direction do not protrude from the surface of the reinforcing member.

[0078] This configuration allows reinforcing members to be placed in areas of the floor where friction with the wheels is more likely to occur than in other areas. Therefore, areas of the floor that are prone to wear due to friction with the wheels can be properly protected.

[0079] Furthermore, it is preferable that the transport equipment determines the direction change position by having the transport vehicle pre-set a set number of direction change positions relative to the same reference position in the direction change position distribution process, and by sequentially adopting the set number of direction change positions each time the transport vehicle performs the direction change relative to the reference position.

[0080] This configuration allows for the appropriate distribution of direction change positions during multiple direction changes based on the same reference position, using relatively simple calculations.

[0081] Furthermore, the transport equipment is configured such that the transport vehicle determines the direction change position according to a specific distributed algorithm. The distribution algorithm is preferably configured to determine the direction change position such that, in multiple direction changes based on the same reference position, the distribution of the number of direction changes at each direction change position with respect to the distance between the reference position and the direction change position follows a normal distribution.

[0082] This configuration allows for a relatively small variation in the direction change position relative to the reference position during multiple direction changes based on the same reference position, while also appropriately distributing the direction change positions during multiple direction changes based on the same reference position. [Industrial applicability]

[0083] The technology disclosed herein can be used in conveying equipment that includes a transport vehicle that travels on the floor. [Explanation of Symbols]

[0084] 1: Conveying equipment 2: Transport vehicle 4: Reinforcement member 10: Object to be transported 23: Vehicle position recognition device 31: Floor surface 222 :Wheel 231: Detected part 232: Detection unit D3: Up and down direction P: Dispersion range WX: Rotation axis center

Claims

1. A transport vehicle that transports the object to be transported, The floor surface on which the transport vehicle travels, A conveying device equipped with, The transport vehicle comprises wheels that roll on the floor surface and a vehicle position recognition device for recognizing its own position on the floor surface. A sheet-like reinforcing member having a surface with higher wear resistance than the floor surface is placed on the floor surface at a position including the position of the wheels of the transport vehicle when it is in a reference position. The transport vehicle is configured to change direction based on the vehicle position recognition result by the vehicle position recognition device, using the preset reference position as a reference. The position at which the transport vehicle changes direction is defined as the direction change position. The transport vehicle performs a direction change position distribution process in which, during multiple direction changes based on the same reference position, the direction change positions are distributed within a distribution range set so that the wheels of the transport vehicle during the direction change do not protrude from the surface of the reinforcing member. The transport vehicle is a transport device that, in the direction change position distribution process, determines the direction change position such that the distribution of the number of direction changes at each direction change position with respect to the distance between the reference position and the direction change position in multiple direction changes based on the same reference position follows a normal distribution.

2. The transport vehicle sets the direction change position with respect to the reference position, and performs the direction change with the axis passing through the direction change position and along the vertical direction as the pivot axis, according to claim 1.

3. The aforementioned reference position is the position of each of the multiple detection units arranged on the floor surface. The transport vehicle is configured to travel along a path set to connect a plurality of the detected units, The transport equipment according to claim 1 or claim 2, wherein the vehicle position recognition device is configured to recognize the vehicle position based on the detection of each of the detected parts.

4. The transport vehicle, in the direction change position distribution process, pre-sets a set number of direction change positions for the same reference position, and determines the direction change position by sequentially adopting the set number of direction change positions each time the direction change is performed with respect to the reference position, according to claim 1 or claim 2.

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