Conveying system

Abstract

A transport system according to the present invention comprises a plurality of transport cars that travel along a track and transport cargo and a controller that controls the travel of the plurality of transport cars. The track includes a principal track and first branch tracks that branch from the principal track via different branch points. The controller performs advancement control that makes the transport cars advance onto respective first branch tracks. The advancement control makes the transport cars advance onto respective first branch tracks in an order of priority that corresponds to advancement information about the advancement state of the transport cars onto the first branch tracks.

Description

Technical Field

[0001] One aspect of the present invention relates to a conveying system.

Background Art

[0002] There is known a conveying system including a plurality of carrier vehicles traveling along a track and a controller for controlling the traveling of the plurality of carrier vehicles. As a technology related to such a conveying system, for example, Patent Document 1 describes a system for preferentially allowing a carrier vehicle to enter a downstream branch track among a plurality of branch tracks of a track. In this conveying system, the carrier vehicle delivers loads to loading / unloading ports provided along each of the plurality of branch tracks.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the conveying system as described above, since the carrier vehicle is preferentially allowed to enter the downstream branch track, if the number of carrier vehicles that can enter each branch track is insufficient due to some circumstances, the frequency of the carrier vehicle entering the upstream branch track decreases. In this case, the frequency of load delivery to the delivery port provided along the upstream branch track decreases. That is, the conveyance of loads from a specific delivery port may be delayed, and smooth load conveyance by the carrier vehicle may become difficult.

[0005] One aspect of the present invention has been made in view of the above circumstances, and an object thereof is to provide a conveying system capable of smoothly conveying loads by a carrier vehicle.

Means for Solving the Problems

[0006] (1) A transport system according to one aspect of the present invention is a transport system comprising a plurality of transport vehicles that travel along a track and transport cargo, and a controller that controls the movement of the plurality of transport vehicles. The track has a first main track and a plurality of branch tracks that branch off from the first main track via different branching points. The controller performs entry control to allow the transport vehicles to enter each of the plurality of branch tracks from the first main track. In the entry control, the controller allows the transport vehicles to enter the branch tracks in an order of priority according to entry information regarding the entry status of each transport vehicle into the plurality of branch tracks.

[0007] In this transport system, transport vehicles are allowed to enter the branch tracks from the first main track in a priority order based on entry information regarding the entry status of each transport vehicle into multiple branch tracks. This makes it possible to allow transport vehicles to enter each of the multiple branch tracks, for example, to prevent a situation where there is always a shortage of transport vehicles on a particular branch track. As a result, it is possible to suppress a decrease in the frequency of cargo transfers to transfer ports located along a particular branch track (slowness in cargo transport from a particular transfer port), and transport vehicles can transport cargo smoothly.

[0008] (2) In the transport system described in (1) above, the entry information may include information indicating the number of transport vehicles present on each branch track. In the entry control, based on the entry information, transport vehicles may be given priority to enter the branch track with the fewest transport vehicles among multiple branch tracks. In this case, the situation in which there is always a shortage of transport vehicles on a particular branch track can be specifically prevented.

[0009] (3) In the transport system described in (2) above, in the entry control, if there are multiple branch tracks with the fewest number of transport vehicles, the transport vehicle may be directed to the branch track corresponding to the branch point located furthest downstream of the first main track among the multiple branch tracks. This allows the transport vehicle to enter each branch track more smoothly compared to the case where the transport vehicle is given priority to enter the branch track that branches off from the upstream side of the first main track among the multiple branch tracks.

[0010] (4) In the transport system described in (1) above, the entry information may include information regarding the branch track into which the first transport vehicle entered. In the entry control, if there is another branch point adjacent to the branch point of the branch track into the first main track, the second transport vehicle, which follows immediately after the first transport vehicle, may enter the branch track corresponding to the other branch point. If there is no other branch point, the second transport vehicle may enter the branch track corresponding to the branch point located furthest downstream on the first main track. In this case, it becomes possible to have multiple transport vehicles enter each branch track equally.

[0011] (5) In the transport system described in (1) above, the entry information may include information indicating the number of transport vehicles present on each branch track. In the entry control, based on the entry information, transport vehicles may be allowed to enter branch tracks where the number of transport vehicles present is less than the set number. In the entry control, if there are no branch tracks where the number of transport vehicles present is less than the set number, transport vehicles may be kept waiting on the first main track. In this case, a situation in which transport vehicles enter a particular branch track in a concentrated manner can be avoided.

[0012] (6) In the transport system described in (5) above, in the entry control, if, after the transport vehicles are waiting on the first main track, there are multiple branch tracks where the number of transport vehicles is less than the set number, the waiting transport vehicles may be allowed to enter the branch track corresponding to the branch point located furthest downstream of the first main track among the multiple branch tracks. This allows the transport vehicles to enter the branch tracks more smoothly compared to the case where the transport vehicles are preferentially allowed to enter the branch tracks that branch off from the upstream side of the first main track among the multiple branch tracks.

[0013] (7) In the transport system described in (5) or (6) above, the entry control starts the entry of transport vehicles waiting on the first main track into at least one of the multiple branch tracks based on the timing when the number of transport vehicles on the branch track corresponding to the furthest downstream branch point decreases. This allows transport vehicles to enter the branch tracks more smoothly compared to the case where transport vehicles are given priority to enter the branch track that branches off from the upstream side of the first main track among the multiple branch tracks.

[0014] (8) In the transport system described in any one of the above paragraphs (2) to (7), the track may have a second main track. Multiple branch tracks may be connected to the second main track via different junctions. The controller may perform launch control to launch each transport vehicle stopped at its respective stopping position on the multiple branch tracks toward the second main track for each of the multiple branch tracks. In entry control, the number of transport vehicles on the branch track corresponding to the destination may be increased by one at the time the destination of the transport vehicle is determined. In launch control, the number of transport vehicles on the branch track may be decreased by one at the time the transport vehicle is launched on the branch track. In this case, the above-mentioned effect of enabling the transport vehicles to transport the load smoothly can be concretely realized.

[0015] (9) In the transport system described in any one of the above paragraphs (1) to (8), the track may have a second main track and a reserve branch track. Multiple branch tracks may be connected to the second main track via different junctions. The reserve branch track may branch off from the first main track via a reserve junction, which is another junction located downstream of the multiple junctions, and be connected to the second main track via a reserve junction, which is another junction located upstream of the multiple junctions. In the entry control, if it is impossible to transfer the load on at least one of the multiple branch tracks, the transport vehicle scheduled to enter the branch track where load transfer is impossible may be directed to enter the reserve branch track instead. This makes it possible to suppress a decrease in transport capacity by using the reserve branch track even when it is impossible to transfer the load on at least one of the multiple branch tracks.

[0016] (10) In the conveying system described in (9) above, the track may have an auxiliary branch track. The auxiliary branch track branches from the second main track through an auxiliary branch point which is a branch point located downstream of a plurality of merging points, and may be connected to the first main track through an auxiliary merging point which is a merging point located upstream of the plurality of branch points. The controller may cause the carrier that has entered the preliminary branch track to enter the auxiliary branch track. In this case, for example, even when there is a trouble in the interface part of the carrier or the conveyed item on the branch track and the transfer of the load is impossible, it is possible to further suppress the reduction of the conveying capacity of the conveying system.

Advantages of the Invention

[0017] According to one aspect of the present invention, it is possible to provide a conveying system in which a carrier can smoothly convey a load.

Brief Description of the Drawings

[0018] [Figure 1] FIG. 1 is a schematic plan view showing a conveying system according to an embodiment. [Figure 2] FIG. 2 is a side view showing a carrier of the conveying system of FIG. 1. [Figure 3] FIG. 3 is a schematic plan view showing the first building side of the conveying system of FIG. 1. [Figure 4] FIG. 4 is a schematic plan view for explaining an example of access control in the conveying system of FIG. 1. [Figure 5] FIG. 5 is a schematic plan view for explaining the continuation of FIG. 4. [Figure 6] FIG. 6 is a schematic plan view for explaining an example of access control in the conveying system of FIG. 1. [Figure 7] FIG. 7 is a schematic plan view for explaining the continuation of FIG. 6. [Figure 8] FIG. 8 is a schematic plan view showing the first building side of the conveying system according to the fourth embodiment. [Figure 9] FIG. 9 is a schematic plan view showing the first building side of the conveying system according to the fifth embodiment.

Modes for Carrying Out the Invention

[0019] Hereinafter, an embodiment will be described with reference to the drawings. In the description of the drawings, the same or corresponding elements are denoted by the same reference numerals, and redundant descriptions are omitted. The dimensional ratios in the drawings do not necessarily match those in the description.

[0020] The first embodiment will be described. As shown in FIG. 1, the transport system 1 according to the first embodiment is a system that performs two-point transport in which the transport source and the transport destination are patterned. The transport system 1 performs inter-building transport for delivering loads between the first building F1 and the second building F2. The transport system 1 includes a plurality of transport vehicles 10 and a controller 20. The transport vehicle 10 travels along the track 3 and transports the load. The transport vehicle 10 is configured to be able to transfer the load. The transport vehicle 10 is an overhead traveling unmanned transport vehicle. The transport vehicle 10 is also referred to as, for example, a trolley (transport trolley), an overhead traveling vehicle (overhead traveling trolley), or a traveling vehicle (traveling trolley). The number of transport vehicles 10 included in the transport system 1 is, for example, about 50, and varies depending on the transport requirement amount and the transport distance.

[0021] As shown in FIG. 2, the transport vehicle 10 includes a traveling trolley 144, a power supply trolley 145 that receives power supply from the track 3, a θ drive 147, and a lateral feed unit 146 for laterally feeding the lower part with respect to the track 3. The θ drive 147 controls the posture of the load L by rotating the lifting drive unit 148 in the horizontal plane. The lifting drive unit 148 raises and lowers the lifting table 149 that holds the load L, and delivers the load L to and from the delivery port 4. The lifting table 149 chucks at the flange 124 part at the upper part of the load L. Note that the lateral feed unit 146 and the θ drive 147 may not be provided. The load L is, for example, a container that stores a plurality of semiconductor wafers, but may also be a glass substrate, general parts, etc.

[0022] Track 3 is laid, for example, on the ceiling. Track 3 is supported by pillars 141. Track 3 is a predetermined route for the transport vehicle 10 to travel on. Track 3 is a one-way route. In other words, in the transport system 1, the direction of travel (forward direction) of the transport vehicle 10 on track 3 is fixed to one direction, and travel in the opposite direction is prohibited. Track 3 has a closed track layout that is not affected by anything outside of track 3. Hereinafter, the terms "upstream" and "downstream" correspond to "upstream" and "downstream" in the direction of travel of the transport vehicle 10, respectively.

[0023] In the example shown in Figure 1, track 3 includes main tracks 31 and 32, four first branch tracks 33a, 33b, 33c, and 33d that branch off from main track 32 and merge with main track 31, and four second branch tracks 34a, 34b, 34c, and 34d that branch off from main track 31 and merge with main track 32. Main tracks 31 and 32 are tracks that span between building 1 F1 and building 2 F2. The length of main tracks 31 and 32 is, for example, 200m. Between building 1 F1 and building 2 F2, main tracks 31 and 32 are enclosed and closed off by a wall (not shown). Main tracks 31 and 32, first branch tracks 33a to 33d, and second branch tracks 34a to 34d constitute a circular track for multiple transport vehicles 10 to travel in a loop.

[0024] The first branch tracks 33a to 33d are located within Building 1 F1. The first branch tracks 33a to 33d extend in parallel. The first branch tracks 33a to 33d are arranged in a comb-like pattern between the parallel main tracks 31 and 32. The first branch tracks 33a to 33d are located upstream of the main track 31 (downstream of the main track 32) in this order. The second branch tracks 34a to 34d are located in Building 2 F2. The second branch tracks 34a to 34d extend in parallel. The second branch tracks 34a to 34d are arranged in a comb-like pattern between the parallel main tracks 31 and 32. The second branch tracks 34a to 34d are located upstream of the main track 32 (downstream of the main track 31) in this order.

[0025] Next, the configuration and control of the transport system 1 will be described in detail. In the following description, the configuration and control on the first building F1 side will be explained, and the configuration and control on the second building F2 side will be similar, so the explanation will be omitted as appropriate.

[0026] As shown in Figure 3, the points where the first branch tracks 33a to 33d merge with the main track 31 are the merging points 35a, 35b, 35c, and 35d. Each of the first branch tracks 33a to 33d is connected to the main track 31 via the respective merging points 35a, 35b, 35c, and 35d. In other words, track 3 has multiple merging points 35a to 35d, which are located apart from each other on the main track 31. The main track 31 is joined by each of the first branch tracks 33a to 33d via the different merging points 35a, 35b, 35c, and 35d. For example, the portion of track 3 downstream from merging point 35a is considered to be the main track 31, and upstream of that, it is considered to merge with the first branch track 33a. The first branch tracks 33a to 33d each connect to the main track 31 via different confluence points 35a to 35d. The confluence points 35a to 35d are separated by a predetermined distance from each other on the main track 31.

[0027] The points where the first branch tracks 33a to 33d branch off from the main track 32 are branching points 36a, 36b, 36c, and 36d. Each of the first branch tracks 33a to 33d is connected to the main track 32 via branching points 36a, 36b, 36c, and 36d, respectively. In other words, track 3 has multiple branching points 36a to 36d, which are located far apart from each other on the main track 32. The main track 32 branches off to each of the first branch tracks 33a to 33d via different branching points 36a, 36b, 36c, and 36d. For example, the part of track 3 upstream from branching point 36a is considered to be the main track 32, and downstream it is considered to branch off to the first branch track 33a. Each of the first branch tracks 33a to 33d is connected to the main track 32 via different branching points 36a to 36d. The branching points 36a to 36d are separated by a predetermined distance from each other on the main track 32.

[0028] A "junction" is a point where a branch track connects to the main track. A "junction" is a point where a branch track leads to the main track. A "junction" is one of these connection points for entering the main track from a branch track. A "junction" is a point where a branch track connects to the main track. A "junction" is a point where a branch track leads to the branch track. A "junction" is one of these connection points for entering the branch track from the main track. In the example shown in Figure 3, main track 31 corresponds to the second main track, main track 32 corresponds to the first main track, and the first branch tracks 33a to 33d correspond to the branch tracks.

[0029] Each of the first branch tracks 33a to 33d has a stopping position corresponding to a transfer port 4 for the transport vehicle 10 to transfer the load L. The transfer ports 4 are located along each of the first branch tracks 33a to 33d. The transfer ports 4 are provided, for example, on a conveyor (not shown) that transports the load L. The transfer ports 4 have an unloading port 41 and a loading port 42.

[0030] The unloading port 41 is a port for unloading cargo L from the transport vehicle 10. At the unloading port 41, cargo L is unloaded between the time it is placed and the arrival of the next transport vehicle 10. The unloading port 41 is located upstream of the loading port 42 at a predetermined interval. In other words, the loading port 42 is located downstream of the unloading port 41 at a predetermined interval. The loading port 42 is a port for loading cargo L onto the transport vehicle 10. The loading port 42 can accommodate cargo L being brought into the port over a span where multiple transport vehicles 10 arrive in succession. The unloading port 41 and the loading port 42 are not particularly limited, and various known ports can be used.

[0031] As shown in Figure 3, the controller 20 is an electronic control unit consisting of a CPU (Central Processing Unit), ROM (Read Only Memory), and RAM (Random Access Memory), etc. The controller 20 can be configured as software, for example, in which a program stored in ROM is loaded onto RAM and executed by the CPU. The controller 20 may also be configured as hardware, such as electronic circuits. The controller 20 communicates with multiple transport vehicles 10 and controls the movement of the multiple transport vehicles 10.

[0032] The controller 20 executes launch control for each transport vehicle 10 stopped at a stop position corresponding to the transfer port 4 of each of the first branch tracks 33a to 33d (in this case, a stop position corresponding to the loading port 42), causing them to start moving toward the main track 31 for each of the first branch tracks 33a to 33d. In the following, the stop position corresponding to the loading port 42 may also be simply referred to as the "stop position". The upstream and downstream of the launch control correspond to the upstream and downstream of the main track 31, and the upstream and downstream of the entry control correspond to the upstream and downstream of the main track 32.

[0033] In the starting control, the transport vehicle 10 stopped on the downstream first branch track 33 of the first branch tracks 33a to 33d is started at the same time as, or before, the transport vehicle 10 stopped on the upstream first branch track 33. Specifically, in the starting control, the transport vehicle 10 stopped on the first branch track 33d is started at the same time as, or before, the transport vehicle 10 stopped on the first branch track 33c. The transport vehicle 10 stopped on the first branch track 33c is started at the same time as, or before, the transport vehicle 10 stopped on the first branch track 33b. The transport vehicle 10 stopped on the first branch track 33b is started at the same time as, or before, the transport vehicle 10 stopped on the first branch track 33a.

[0034] More specifically, in the launch control, each stopped transport vehicle 10 is launched (forced launch) at timings that are repeated at regular intervals for each of the first branch tracks 33a to 33d, regardless of whether or not a load L is loaded. For example, in the launch control, a pitch timer starts counting down from a reference pitch time for each of the first branch tracks 33a to 33d. When the pitch timer count reaches 0, the transport vehicle 10 stopped at the stopping position is launched, and the pitch timer count is reset to the reference pitch time. Then, the countdown continues using the pitch timer. The reference pitch time may be a predetermined fixed value or a variable value. In this embodiment, the time axis of the pitch timer for each of the first branch tracks 33a to 33d is staggered so that the transport vehicle 10 stopped on the downstream first branch track 33 is launched first.

[0035] The controller 20 performs entry control to sequentially move each of the multiple transport vehicles 10 traveling on the main track 32 from the main track 32 to each of the first branch tracks 33a to 33d, in order from downstream to upstream. Specifically, in the entry control, the controller moves the transport vehicle 10 into the first branch track 33a, then into the first branch track 33b, then into the first branch track 33c, then into the first branch track 33d, and so on, repeating the entry of the transport vehicles 10.

[0036] In the approach control, destination determination control is performed to determine (guide) the destination of a transport vehicle 10 traveling in a specific section R upstream of each branch point 36a to 36d on the main track 32. The specific section R is a straight section close to each branch point 36a to 36d. The specific section R is not limited to a straight section, but may include curves, and may be various types of sections. The specific section R is not particularly limited as long as it is upstream of each branch point 36a to 36d. In the destination determination control, the transfer port 4 of the destination (in this case, one of the unloading ports 41 of the first branch track 33a to 33d) is determined.

[0037] The controller 20 keeps track of the number of transport vehicles 10 present on each of the first branch tracks 33a to 33d (number of vehicles entering). Specifically, in entry control, when the destination is determined by the destination determination control described above, the controller 20 increases the number of transport vehicles 10 present on any of the first branch tracks 33a to 33d corresponding to that destination by one (count up). In departure control, when a transport vehicle 10 that is stopped at any of the stopping positions on the first branch tracks 33a to 33d is started, the controller 20 decreases the number of transport vehicles 10 present on any of the first branch tracks 33a to 33d by one at the time of departure (count down).

[0038] Returning to Figure 1, the controller 20 performs virtual coupling control, which includes the aforementioned starting control and entry control, for each group of transport vehicles 10, which includes multiple transport vehicles (four in this case) corresponding to the number of first branch tracks 33a to 33d. The controller 20 makes the multiple transport vehicles 10 travel along the circular track (main tracks 31, 32, first branch tracks 33a to 33d, and second branch tracks 34a to 34d) so that the circumference distance or circumference time is the same. For example, in entry control, the controller 20 directs a transport vehicle 10 that has entered the first branch track 33d to enter the second branch track 34a, a transport vehicle 10 that has entered the first branch track 33c to enter the second branch track 34b, a transport vehicle 10 that has entered the first branch track 33b to enter the second branch track 34c, and a transport vehicle 10 that has entered the first branch track 33a to enter the second branch track 34d. Furthermore, in the entry control, a transport vehicle 10 that has entered the second branch track 34d is moved to the first branch track 33a, a transport vehicle 10 that has entered the second branch track 34c is moved to the first branch track 33b, a transport vehicle 10 that has entered the second branch track 34b is moved to the first branch track 33c, and a transport vehicle 10 that has entered the second branch track 34a is moved to the first branch track 33d.

[0039] Next, we will explain in detail the entry control by the controller 20.

[0040] In the entry control, the transport vehicles 10 are guided from the main track 32 to the first branch tracks 33a to 33d in a priority order corresponding to the entry information regarding the entry status of each transport vehicle to the first branch tracks 33a to 33d. Specifically, in the destination determination control included in the entry control, the transfer port 4 to which the transport vehicle 10 will transfer the load is determined in a priority order corresponding to the entry status. In the entry control, the transport vehicle 10 is guided to one of the first branch tracks 33a to 33d corresponding to the transfer port 4 determined in the destination determination control.

[0041] For example, in entry control, entry information is acquired that includes information indicating the number of transport vehicles 10 present on each of the first branch tracks 33a to 33d. In destination determination control, based on the acquired entry information, the transfer port 4 of the first branch track 33 with the fewest number of transport vehicles 10 among the first branch tracks 33a to 33d is determined as the destination for the transport vehicle 10. In entry control, the transport vehicle 10 is made to enter the first branch track 33 corresponding to the determined destination. In other words, in entry control, the transport vehicle 10 is made to enter the first branch track 33 with the fewest number of transport vehicles 10 among the first branch tracks 33a to 33d. Furthermore, in the entry control, if there are multiple first branch tracks 33 with the fewest number of transport vehicles 10, the transfer port 4 of the first branch track 33 corresponding to the branch point 36 located furthest downstream of the main track 32 among the multiple first branch tracks 33 is determined as the destination for the transport vehicle 10. In the entry control, the transport vehicle 10 is guided into the first branch track 33 corresponding to the determined destination. In other words, in the entry control, if there are multiple first branch tracks 33 with the fewest number of transport vehicles 10, the transport vehicle 10 is guided into the first branch track 33 among the multiple first branch tracks 33a to 33d that corresponds to the branch point 36 located furthest downstream of the main track 32.

[0042] Furthermore, in the destination determination control, if there are no first branch tracks 33 with fewer than the set number of transport vehicles 10, the destination transfer port 4 is not determined. In this case, in the entry control, the transport vehicles 10 are kept waiting on the main track 32 without entering any of the first branch tracks 33. In the entry control, entry of the transport vehicles 10 waiting on the main track 32 to at least one of the multiple first branch tracks 33 is initiated based on the timing when the number of transport vehicles 10 present on the first branch track 33a corresponding to the furthest downstream junction 36a decreases (the timing when the pitch timer count reaches 0). In this entry control, the countdown of the transport vehicles 10 present on the first branch track 33a corresponding to the furthest downstream junction 36a is used as a trigger to start destination determination control for the transport vehicles 10 waiting on the main track 32.

[0043] The set number of units is any number set by the user, and it is sufficient that it is less than or equal to the upper limit of the number of transport vehicles 10 that can be present on each first branch track 33. For example, the set number of units may be one or two or more. Also, there may be cases where the number of transport vehicles 10 present on the first branch track 33a does not decrease when the pitch timer count reaches zero. In this case as well, the entry control may initiate entry of the transport vehicles 10 waiting on the main track 32 to at least one of the multiple first branch tracks 33.

[0044] Figure 4 is a schematic plan view illustrating an example of entry control in the transport system 1. Figure 5 is a schematic plan view continuing from Figure 4. In the example shown in Figure 4, transport vehicles 10a to 10c are traveling to approach a specific section R. Transport vehicles 10d to 10f are located at the loading ports 42 of the first branch tracks 33a to 33c, respectively. That is, there is one transport vehicle 10 on each of the first branch tracks 33a to 33c, and there are zero transport vehicles 10 on the first branch track 33d.

[0045] In a situation like the one shown in Figure 4, for example, the following entry control is performed. First, when the transport vehicle 10a is located in a specific section R, the destination determination control determines the transfer port 4 of the first branch track 33d, which has the fewest number of transport vehicles 10 present (0), as the destination for the transport vehicle 10a. At this time, the controller 20 counts up the number of transport vehicles 10 present on the first branch track 33d. In the entry control, the transport vehicle 10a is made to enter the first branch track 33d.

[0046] Next, when the transport vehicle 10b is located in a specific section R, the destination determination control determines the transfer port 4 of the first branch track 33a, which corresponds to the branch point 36a located furthest downstream of the main track 32, as the destination for the transport vehicle 10b, among the first branch tracks 33a to 33d where there is one transport vehicle 10 present. At this time, the controller 20 counts up the number of transport vehicles 10 present on the first branch track 33a. In the entry control, the transport vehicle 10b is made to enter the first branch track 33a.

[0047] Finally, when the transport vehicle 10c is located in a specific section R, the destination determination control determines the transfer port 4 of the first branch track 33b, which corresponds to the branch point 36b located furthest downstream of the main track 32, as the destination for the transport vehicle 10c. This is selected from the first branch tracks 33b to 33d, which have the fewest transport vehicles 10 present (one vehicle). At this time, the controller 20 counts up the number of transport vehicles 10 present on the first branch track 33b. In the entry control, the transport vehicle 10c is made to enter the first branch track 33b. As a result, as shown in Figure 5, the transport vehicle 10a is made to enter the first branch track 33d, the transport vehicle 10b is made to enter the first branch track 33a, and the transport vehicle 10c is made to enter the first branch track 33b.

[0048] Figure 6 is another schematic plan view illustrating an example of entry control. Figure 7 is a schematic plan view continuing from Figure 6. In the example shown in Figure 6, transport vehicles 10a to 10c are traveling within a specific section R to approach multiple branching points 36. Multiple transport vehicles 10 are positioned at all of the unloading ports 41 and loading ports 42 of the first branch tracks 33a to 33d. That is, there are two transport vehicles 10 in each of the first branch tracks 33a to 33d.

[0049] In a situation like the one shown in Figure 6, for example, when the number of set units is 2, the following approach control is performed. First, the number of transport vehicles 10 present on each of the first branch tracks 33a to 33d is the same as the set number, and in the destination determination control, the destination of transport vehicle 10a is not determined. In the approach control, for example, when transport vehicle 10a approaches the end of a specific section R, transport vehicle 10a is decelerated and transport vehicle 10a is made to wait on the main track 32.

[0050] Then, as shown in Figure 7, the launch control causes the transport vehicles 10 located on each of the first branch tracks 33a to 33d to launch one by one in sequence. In the entry control, when the number of transport vehicles 10 on the first branch track 33a corresponding to the branch point 36a located furthest downstream decreases, the destination of the transport vehicle 10a is determined by the destination determination control. As a result, the destination determination control determines the transfer port 4 of the first branch track 33a, which corresponds to the branch point 36a located furthest downstream of the main track 32, as the destination for the transport vehicle 10a, among the first branch tracks 33a to 33d that have the fewest transport vehicles 10 (only one). At this timing, the controller 20 counts up the number of transport vehicles 10 located on the first branch track 33a. In the entry control, the transport vehicle 10a is made to enter the first branch track 33a.

[0051] In destination determination control, the destination of transport vehicle 10b, which follows transport vehicle 10a, is determined to be the transfer port 4 of the first branch track 33b. In entry control, transport vehicle 10b is made to enter the first branch track 33b. In destination determination control, the destination of transport vehicle 10c, which follows transport vehicle 10b, is determined to be the transfer port 4 of the first branch track 33c. In entry control, transport vehicle 10c is made to enter the first branch track 33c.

[0052] As described above, the transport system 1 allows each transport vehicle 10 to enter the first branch track 33 in a priority order corresponding to the entry information regarding the entry status of each transport vehicle 10 into the multiple first branch track 33. This makes it possible to allow transport vehicles 10 to enter each of the multiple first branch track 33 so as to prevent situations where, for example, there is always a shortage of transport vehicles 10 in a particular first branch track 33. As a result, it is possible to suppress a decrease in the frequency of cargo transfers to and from the transfer ports 4 provided along a particular first branch track 33 (slowing down the transport of cargo from a particular transfer port 4), and enable the transport vehicles 10 to transport cargo smoothly.

[0053] In the transport system 1, the entry information includes information indicating the number of transport vehicles 10 present in each first branch track 33. In the entry control, based on the entry information, the transport vehicle 10 is directed to the first branch track 33 with the fewest transport vehicles 10 present among the multiple first branch tracks 33. In this case, a situation in which there is always a shortage of transport vehicles 10 present in a particular first branch track 33 can be specifically prevented.

[0054] In the transport system 1, during entry control, if there are multiple first branch tracks 33 with the fewest number of transport vehicles 10, the transport vehicle 10 is given priority access to the first branch track 33a corresponding to the branch point 36a located furthest downstream of the main track 32 among the multiple first branch tracks 33. This allows the transport vehicle 10 to enter each branch track more smoothly compared to the case where the transport vehicle 10 is given priority access to the first branch track 33 that branches off from the upstream side of the main track 32 among the multiple first branch tracks 33.

[0055] Specifically, compared to the case where the transport vehicle 10 enters the first branch track 33 corresponding to the branch point 36 located upstream of the main track 32, the transport vehicle 10 is less likely to obstruct the movement of other transport vehicles 10 following it, thereby reducing congestion. In the example shown in Figure 4, there is a possibility that a problem occurs on the first branch track 33 into which the transport vehicle 10b is to enter, preventing the transport vehicle 10b from entering. In this case, for example, when the transport vehicle 10b enters the first branch track 33d that branches off from the upstream side of the main track 32, if the transport vehicle 10b stops upstream of the branch point 36, the transport vehicle 10b may obstruct the entry of the transport vehicle 10c immediately following the transport vehicle 10b into the first branch tracks 33a to 33c, potentially causing congestion on the main track 32. In contrast, in this embodiment, as shown in Figure 5, the transport vehicle 10b is made to enter the first branch track 33a, which branches off from the downstream side of the main track 32. This allows the transport vehicle 10b to wait near the branch point 36a located at the downstream side, thereby preventing it from obstructing the movement of the transport vehicle 10c that follows immediately after it. As a result, the transport vehicle 10c can smoothly enter the first branch track 33b to 33d. From the above, the transport vehicle 10 can be made to enter the first branch track 33 more smoothly, and congestion on the main track 32 can be suppressed.

[0056] In the transport system 1, the entry control initiates the entry of transport vehicles 10 waiting on the main track 32 into at least one of the multiple first branch tracks 33 based on the timing when the number of transport vehicles 10 present on the first branch track 33 corresponding to the furthest downstream branch point 36 decreases. This allows the transport vehicles 10 to enter the first branch tracks 33 more smoothly compared to the case where the transport vehicles 10 are preferentially guided into the first branch tracks 33 that branch off from the upstream side of the main track 32.

[0057] In the transport system 1, the track 3 has a main track 31. Multiple first branch tracks 33 are connected to the main track 31 via different junctions 35. The controller 20 performs launch control to launch each transport vehicle 10, which has stopped at each of the multiple first branch tracks 33, toward the main track 31 for each of the multiple first branch tracks 33. In entry control, at the time the destination of the transport vehicle 10 is determined, the number of transport vehicles 10 present on the first branch track 33 corresponding to that destination is increased by one. In launch control, at the time the transport vehicle 10 is launched on the first branch track 33, the number of transport vehicles 10 present on that first branch track 33 is decreased by one. In this case, the above-mentioned effect of enabling the transport vehicles 10 to smoothly transport the load can be concretely realized.

[0058] Next, a second embodiment will be described. In the first embodiment described above, the entry control was described as allowing the transport vehicle 10 to enter the first branch track 33 of the first branch tracks 33a to 33d that has the fewest transport vehicles 10 present, but this is not limited to this. In the entry control according to the second embodiment, each transfer port 4 of the first branch tracks 33a to 33d may be determined as the transport destination for the transport vehicle 10 in order from the downstream side to the upstream side of the main track 32 (cyclically), and the transport vehicle 10 may be allowed to enter the first branch track 33 of the determined transport destination in order.

[0059] More specifically, in the entry control according to the second embodiment, entry information including information about the first branch track 33 (entry branch track) into which the transport vehicle 10 (first transport vehicle) enters may be acquired. In the destination determination control, based on the acquired entry information, if there is another branch point 36 adjacent to the branch point 36 of the first branch track 33 into which the transport vehicle 10 entered on the main track 32, the transfer port 4 of the first branch track 33 corresponding to the other branch point 36 may be determined as the destination for another transport vehicle 10 (second transport vehicle) that follows immediately after the transport vehicle 10. In the entry control, another transport vehicle 10 may be made to enter the first branch track 33 of the determined destination. In other words, in the entry control, if there is another branching point 36 adjacent to the branching point 36 of the first branch track 33 into which the transport vehicle 10 has entered on the main track 32, another transport vehicle 10 may be made to enter the first branch track 33 corresponding to the other branching point 36.

[0060] In addition, in the destination determination control of the entry control according to the second embodiment, if there is no other branching point 36, the transfer port 4 of the first branch track 33a corresponding to the branching point 36a located on the downstream side of the main track 32 may be determined as the destination for another transport vehicle 10. In the entry control, another transport vehicle 10 may be made to enter the first branch track 33 of the determined destination. In other words, in the entry control, if there is no other branching point 36, another transport vehicle 10 may be made to enter the first branch track 33a corresponding to the branching point 36a located on the downstream side of the main track 32.

[0061] In this case, for example, in the situation shown in Figure 4, if we assume that the transport vehicle 10f has just entered the first branch track 33c, the following entry control according to the second embodiment will be executed. First, in the destination determination control, since there is another branch point 36d adjacent to the branch point 36c of the first branch track 33c into which the transport vehicle 10f entered on the main track 32, the transfer port 4 of the first branch track 33d corresponding to the other branch point 36d is determined as the destination for the transport vehicle 10a that follows immediately after the transport vehicle 10f. In the entry control, the transport vehicle 10a is made to enter the first branch track 33d.

[0062] Next, in the destination determination control, since there is no branching point 36 upstream of branching point 36d of the first branch track 33d into which the transport vehicle 10a entered on the main track 32, the transfer port 4 of the first branch track 33a, which corresponds to branching point 36a located furthest downstream on the main track 32, is determined as the destination for the transport vehicle 10b. In the entry control, the transport vehicle 10b is made to enter the first branch track 33a.

[0063] Finally, in the destination determination control, since there is another branch point 36b adjacent to the branch point 36a of the first branch track 33a into which the transport vehicle 10b entered on the main track 32, the transfer port 4 on the first branch track 33b corresponding to the other branch point 36b is determined as the destination for the transport vehicle 10c that follows immediately after the transport vehicle 10b. In the entry control, the transport vehicle 10c is made to enter the first branch track 33b.

[0064] As described above, the entry control is executed so that the transport vehicles 10 enter the first branch track 33a to 33d in that order, and immediately after the transport vehicle 10 enters the first branch track 33d, the transport vehicle 10 enters the first branch track 33a. As a result, the transport vehicle 10a enters the first branch track 33d, the transport vehicle 10b enters the first branch track 33a, and the transport vehicle 10c enters the first branch track 33b.

[0065] According to the transport system 1 that performs entry control according to the second embodiment, it is possible to allow multiple transport vehicles 10 to enter each first branch track 33 evenly. As a result, a decrease in the number of transport vehicles 10 starting from the first branch tracks 33a to 33d is suppressed, and a shortage of transport vehicles 10 on the second branch tracks 34a to 34d is suppressed. Consequently, a decrease in the frequency of load transfer between the transport vehicles 10 and the transfer ports 4 provided along the second branch tracks 34a to 34d is suppressed, and a decrease in transport capacity can be suppressed.

[0066] Next, a third embodiment will be described. In the entry control according to the third embodiment, based on the acquired entry information, the transport vehicle 10 may be made to enter the first branch track 33 where the number of existing transport vehicles 10 is less than the set number. More specifically, in the destination determination control, based on the acquired entry information, the transfer port 4 of the first branch track 33 where the number of existing transport vehicles 10 is less than the set number may be determined as the destination for the transport vehicle 10. In the entry control, the transport vehicle 10 may be made to enter the first branch track 33 of the determined destination.

[0067] In this case, for example, in the situation shown in Figure 4, the entry control according to the third embodiment is executed. First, if the number of set units is 1, the destination determination control determines the transfer port 4 of the first branch track 33d, where there are 0 existing transport vehicles 10, as the destination for transport vehicle 10a. In the entry control, transport vehicle 10a is made to enter the first branch track 33d. Also, if the number of set units is 2, the destination determination control determines one of the transfer ports 4 of the first branch tracks 33a to 33d, where there is 1 or fewer existing transport vehicles 10, as the destination for transport vehicle 10a. In the entry control, transport vehicle 10a is made to enter the first branch track 33, which is the determined destination.

[0068] For example, in the destination determination control of the entry control according to the third embodiment, if, after the transport vehicle 10 is placed on the main track 32, multiple first branch tracks 33 occur where the number of transport vehicles 10 present is less than the set number, the transfer port 4 of the first branch track 33 corresponding to the branch point 36 located furthest downstream of the main track 32 may be determined as the destination for the waiting transport vehicle 10. In the entry control, the transport vehicle 10 may be brought to the determined destination. In other words, in the entry control, if, after the transport vehicle 10 is placed on the main track 32, multiple first branch tracks 33 occur where the number of transport vehicles 10 present is less than the set number, the transport vehicle 10 may be brought to the first branch track 33 corresponding to the branch point 36 located furthest downstream of the main track 32.

[0069] In this case, for example, in the situation shown in Figure 7, the following entry control according to the third embodiment is executed. First, in the destination determination control, the transfer port 4 of the first branch track 33a, which corresponds to the branch point 36a located furthest downstream of the main track 32 among the first branch tracks 33a to 33d, is determined as the destination for the transport vehicle 10a waiting on the main track 32. In the entry control, the transport vehicle 10a is made to enter the determined destination.

[0070] In the entry control according to the third embodiment, based on entry information, the transport vehicles 10 are allowed to enter the first branch track 33 where the number of transport vehicles 10 present is less than the set number. In the entry control, if there are no first branch tracks 33 where the number of transport vehicles 10 present is less than the set number, the transport vehicles 10 are made to wait on the main track 32. This makes it possible to avoid a situation where transport vehicles 10 enter a particular first branch track 33 in a concentrated manner. In other words, since it is suppressed that the number of transport vehicles 10 entering each first branch track 33 exceeds the number that can enter, congestion on the first branch tracks 33 can be suppressed. As a result, a decrease in the transport volume in the transport system can be suppressed.

[0071] In the entry control according to the third embodiment, after the transport vehicle 10 is placed on the main track 32, if there are multiple first branch tracks 33 where the number of transport vehicles 10 is less than the set number, the waiting transport vehicle 10 is placed on the first branch track 33a corresponding to the branch point 36a located furthest downstream of the main track 32 among the multiple first branch tracks 33. This allows the transport vehicle 10 to enter the first branch track 33 more smoothly compared to the case where the transport vehicle 10 is preferentially placed on the first branch track 33 that branches off from the upstream side of the main track 32 among the multiple first branch tracks 33.

[0072] Next, the fourth embodiment will be described. In the first to third embodiments, the track 3 has main tracks 31, 32, a first branch track 33, and a second branch track 34, but the configuration of the track 3 is not particularly limited. Figure 8 is a schematic plan view showing the transport system 101 according to the fourth embodiment. As shown in Figure 8, the transport system 101 according to the fourth embodiment has a track 103 instead of track 3 (see Figure 3). The track 103 has main tracks 31, 32, a first branch track 33, a second branch track 34, and a reserve branch track 133. The reserve branch track 133 is connected to the main track 32 via a reserve branch point 136, which is another branch point located downstream of the multiple branch points 36a to 36d. The reserve branch track 133 is connected to the main track 31 via a reserve confluence point 135, which is another confluence point located upstream of the multiple confluence points 35a to 35d. Furthermore, the main track 32 branches off to the auxiliary branch track 133 via the auxiliary junction 136. Also, for example, the portion of track 103 upstream of the auxiliary junction 136 is considered to be the main track 32, and downstream of that it is considered to branch off to the auxiliary branch track 133.

[0073] In the transport system 101 according to the fourth embodiment, in the entry control, if it is impossible to transfer a load on at least one of the multiple first branch tracks 33, the transport vehicle 10 scheduled to enter the first branch track 33 where load transfer is impossible is directed to enter the reserve branch track 133 instead. This makes it possible to suppress a decrease in transport capacity by utilizing the reserve branch track 133 even when it is impossible to transfer a load on at least one of the multiple first branch tracks 33. Specifically, it makes it possible to suppress congestion caused by the transport vehicle 10 scheduled to enter obstructing the movement of another transport vehicle 10 following behind. The reserve merging point 135 is located at a predetermined distance from the merging point 35a. The reserve junction point 136 is located at a predetermined distance from the junction point 36a.

[0074] In the fourth embodiment of the transport system 101, the transfer port 4 is located along the auxiliary branch track 133. This allows for the transfer of cargo on the auxiliary branch track 133, thereby further suppressing the reduction in the transport capacity of the transport system 1.

[0075] Next, a fifth embodiment will be described. Figure 9 is a schematic plan view showing the transport system 201 according to the fifth embodiment. As shown in Figure 9, the transport system 201 according to the fifth embodiment has a track 203 instead of track 3 (see Figure 3). Track 203 has main tracks 31, 32, a first branch track 33, a second branch track 34, a reserve branch track 133, and an auxiliary branch track 237. The auxiliary branch track 237 is connected to the main track 31 via an auxiliary branch point 236, which is a branching point located downstream of the multiple confluence points 35. That is, the main track 31 branches off to the auxiliary branch track 237 via the auxiliary branch point 236. The auxiliary branch track 237 is connected to the main track 32 via an auxiliary confluence point 235, which is a confluence point located upstream of the multiple branch points 36.

[0076] In the transport system 201 according to the fifth embodiment, in the entry control, a transport vehicle 10 that has entered the reserve branch track 133 may be moved to the auxiliary branch track 237. In this case, for example, even if the interface part of the transport vehicle 10 or the transported goods malfunctions on the first branch track 33 and the transfer of the load becomes impossible, it is possible to further suppress the decrease in transport capacity. Also, if there is an imbalance in the number of transport vehicles 10 on each of the main tracks 31 and 32 between the main track 31 and the main track 32, this imbalance can be resolved by moving a transport vehicle 10 that is not transporting a load L to the auxiliary branch track 237. Note that the above-mentioned reserve branch track 133 and auxiliary branch track 237 may also be provided on the side of the second building F2.

[0077] Although embodiments have been described above, one aspect of the present invention is not limited to the above embodiments, and various modifications are possible without departing from the spirit of the invention.

[0078] In the above embodiment, track 3 includes four first branch tracks 33a to 33d, but the number of first branch tracks may be two, three, or five or more. Similarly, track 3 includes four second branch tracks 34a to 34d, but the number of second branch tracks may be two, three, or five or more.

[0079] In the above embodiment, the vehicle is forcibly started at a fixed interval regardless of whether the load L is loaded or not during the start control, but it may be started only if the load L is loaded. In the above embodiment, destination determination control is performed to determine the destination of the transport vehicle 10 traveling in a specific section R, but destination determination control is not required, and the destination transfer port 4 may be determined at any timing. In the above embodiment, virtual coupling control is performed to control each transport vehicle group including multiple transport vehicles 10, but virtual coupling control is not required.

[0080] In the above embodiment, when the transport vehicle 10 is to enter the first branch track 33 corresponding to the destination during entry control, a problem may occur in the first branch track 33, preventing the transport vehicle 10 from entering the first branch track 33 (i.e., the first branch track 33 is down). In this case, the entry control may cause the transport vehicle 10 to enter the first branch track 33 corresponding to another branch point 36 adjacent to the branch point 36 upstream of the branch point 36 of the first branch track 33. If the branch point 36 of the first branch track 33 where the problem occurred is the branch point 36 located furthest upstream of the main track 32, the transport vehicle 10 may be kept waiting on the main track 32.

[0081] The configurations in the above embodiments are not limited to the shapes described above, and various shapes can be applied. Each configuration in each embodiment can be arbitrarily applied to each configuration in other embodiments. Some of the configurations in the above embodiments can be omitted as appropriate without departing from the gist of one aspect of the present invention. [Explanation of Symbols]

[0082] 1,101,201...Transportation system, 3,103,203...Track, 4...Transfer port, 10,10a~10f...Transport vehicle, 20...Controller, 31...Main track (2nd main track), 32...Main track (1st main track), 33,33a~33d...1st branch track (branch track), 34a~34d...2nd branch track, 35,35a~35d...Merge point, 36,36a~36d...Jump point, 41...Unloading port, 42...Loading port, 133...Alternative branch track, 135...Alternative merge point, 136...Alternative jump point, 235...Auxiliary merge point, 236...Auxiliary jump point, 237...Auxiliary branch track, L...Cargo, R...Specific section.

Claims

1. Multiple transport vehicles that travel along the track and transport cargo, A transport system comprising a controller that controls the movement of multiple transport vehicles, The aforementioned track comprises a first main track and a plurality of branch tracks that branch off from the first main track via different branching points. The controller executes entry control to move the transport vehicle from the first main track to each of the multiple branch tracks. In the aforementioned entry control, the transport vehicles are made to enter the branch track in a priority order corresponding to the entry information regarding the entry status of each transport vehicle into the branch track, The aforementioned entry information includes information indicating the number of transport vehicles present on each branch line track, In the aforementioned entry control, A transport system that, based on the aforementioned entry information, prioritizes the entry of the transport vehicle to the branch track with the fewest existing transport vehicles among multiple branch tracks.

2. In the aforementioned entry control, The transport system according to claim 1, in the case where there are multiple branch tracks with the fewest number of transport vehicles, the transport vehicle is brought into the branch track corresponding to the branch point located furthest downstream of the first main track among the multiple branch tracks.

3. Multiple transport vehicles that travel along a track and transport cargo, A transport system comprising a controller that controls the movement of multiple transport vehicles, The aforementioned track comprises a first main track and a plurality of branch tracks that branch off from the first main track via different branching points. The controller executes entry control to move the transport vehicle from the first main track to each of the multiple branch tracks. In the aforementioned entry control, the transport vehicles are made to enter the branch track in a priority order corresponding to the entry information regarding the entry status of each transport vehicle into the branch track, The aforementioned entry information includes information regarding the branch track into which the first transport vehicle enters, In the aforementioned entry control, If there is another branching point adjacent to the branching point of the approach branching track on the first main track, the second transport vehicle, which follows immediately after the first transport vehicle, enters the branching track corresponding to the other branching point. A transport system that, if no other branching point exists, causes the second transport vehicle to enter the branching track corresponding to the branching point located furthest downstream of the first main track.

4. The aforementioned orbit has a second main orbit, Multiple of the aforementioned branch tracks are connected to the second main track via different junction points. The controller executes a starting control to launch each transport vehicle that has stopped at the respective stopping position of each of the multiple branch tracks toward the second main track, for each of the multiple branch tracks. In the aforementioned entry control, at the time the destination of the transport vehicle is determined, the number of transport vehicles present on the branch track corresponding to that destination is increased by one. The transport system according to any one of claims 1 to 3, wherein the launch control reduces the number of transport vehicles present on the branch track by one at the time the transport vehicle is launched on the branch track.

5. The aforementioned track has a second main track and a backup branch track. Multiple of the aforementioned branch tracks are connected to the second main track via different junction points. The aforementioned auxiliary branch track branches off from the first main track via an auxiliary branch point, which is another branch point located downstream of the plurality of aforementioned branch points, and connects to the second main track via an auxiliary confluence point, which is another confluence point located upstream of the plurality of aforementioned confluence points. In the entry control, if it is impossible to transfer the load on at least one of the multiple branch tracks, the transport vehicle scheduled to enter the branch track where the load transfer is impossible is directed to enter the reserve branch track instead, according to any one of claims 1 to 3.

6. The aforementioned track has an auxiliary branch track, The auxiliary branch track branches off from the second main track via an auxiliary branch point, which is a branching point located downstream of the multiple confluence points, and connects to the first main track via an auxiliary confluence point, which is a confluence point located upstream of the multiple branch points. The transport system according to claim 5, wherein the entry control involves moving the transport vehicle that has entered the auxiliary branch track to enter the auxiliary branch track.

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