JP4503333B2 - Conveyor cart system - Google Patents

Description

  The present invention relates to a collision prevention control for a carriage such as an overhead traveling vehicle, a tracked truck with ground traveling, and an automatic guided vehicle traveling without a track.

  Patent Document 1 describes collision prevention control of a transport carriage such as an automatic guided vehicle. A plurality of points are provided along the travel route, and the transport cart asks the controller to allow the travel of the points before passing the points. When the controller permits the travel, the points are locked and the transport carts travel to the other transport carts. Do not give permission. When the transport cart passes the point, the fact is reported to the controller, and the controller unlocks (unlocks). The problem with this system is that the amount of traffic such as a travel permission request, a travel permission, and an unlock request increases as the number of transport carts increases. Further, as the density of the transport cart with respect to the travel route increases, the probability that travel permission cannot be obtained increases.

Patent Document 1 proposes that the amount of communication is reduced by requesting travel permission collectively for points up to the front of the branching section and the joining section. In addition, since it is difficult to control if the travel permission from a distant place to the branching section and the merging section is given collectively, the traveling permission of the branching section and the merging section is separately given. However, if the travel of a wide range is permitted all at once, the range for locking other transport carts increases and the transport efficiency decreases. Whether to permit travel for each point or to permit travel collectively is a problem of a balance between the amount of communication and the transfer efficiency, and even if the travel permission is collectively granted, it is not a fundamental solution.
JP-A-11-143538

  An object of the present invention is to reduce the amount of communication for collision prevention control of a transport carriage, and to prevent an excessively wide section from being locked and a decrease in transport efficiency.

The present invention, this invention relates to a controller from the transport carriage, requesting travel permission of the section on the travel route, the controller permits the travel to the requested section, the section to the other conveying carriage In the transport cart system to lock,
In a station overcrowded section where stations are arranged at a distance narrower than the collision prevention limit, which is an inter-vehicle distance required to prevent a collision with at least a preceding transport carriage that is stopped, the traveling of the station overcrowded section When passing the request point provided on the front side of the direction , request permission to travel from the transport carriage to the controller,
The transport cart is provided with a collision prevention sensor and a position sensor, and each transport cart travels by monitoring the preceding transport cart with the collision prevention sensor except for a section that requires permission of travel from the transport cart to the controller. Report the position of the trolley to the controller,
When the controller confirms that the requested section is not locked and there are no interfering carriages , the controller permits the carriage that has requested permission to travel , and sets the sections permitted to travel to other sections . Do not allow other transport carts to run by locking the transport cart,
The transport carriage reports to the controller that it has passed the section permitted to travel, and the controller releases the lock based on this report.
In this specification, a point representing a section may be called a point.
The section that requires the controller to allow travel from the transport cart is called a specific section. The specific section includes at least stations (loadports) that are densely packed, and includes other sections such as curves, junctions, and branches. Also good. A specific section may be referred to as an exclusive control section.

  In the present invention, in a specific section such as a station overcrowded portion, the transport carriage travels by monitoring the preceding transport carriage with the collision prevention sensor, and the travel permission / lock control by the controller is received only in the specific section. For this reason, it is possible to drastically reduce communication between the transport carriage and the controller. Furthermore, in a conventional transport cart system, it is necessary to permit travel to a certain extent in a lump in order to reduce the amount of communication and transport efficiency, so it has not yet traveled to a distant transport cart. You will be allowed to travel in the section. In the present invention, the collision prevention sensor ensures that only the front inter-vehicle distance necessary for the conveyance carriage is traveled, thereby improving the conveyance efficiency.

  In the following, an optimum embodiment for carrying out the present invention will be shown.

  1 to 7 show an embodiment and its modifications. In the figure, reference numeral 2 denotes a transport cart system, and the type of the transport cart may be an overhead traveling vehicle, a grounded tracked cart, or a trackless unmanned transport vehicle. In the embodiment, a large-scale transport cart system with a scale of hundreds of transport carts is targeted, 4 is an interbay route and corresponds to a main route, 6 is an intrabay route, and branches from an interbay route 4 at a branching unit 10. And merge at the junction 8. The interbay route 4 and the intrabay route 6 are one-way streets, and shortcuts 7 are provided at appropriate places. The section that is subject to exclusive control by the zone controller 30 as a set section (known to the zone controller 30 and the transport carriage 36 in a specific section) includes the merging section 8, the branch section 10, the curved section 11, the station congestion section 12, The maintenance unit 13 or the like.

  In the merging unit 8, the transport carriage that joins from other directions cannot be detected by the collision prevention sensor, and is therefore subject to travel permission by the zone controller 30. In the branch part 10, since the preceding carriage ahead of the branch side cannot be detected by the collision prevention sensor, it is set as an object of travel permission. In the station overcrowded portion 12, since the stations are arranged at an interval narrower than the collision prevention limit of the collision prevention sensor, traveling is controlled by the zone controller. In the maintenance unit 13, the vehicle is permitted to travel by manually loading or unloading the transport cart, or by moving the ceiling travel rail up and down to insert or remove the transport cart.

  When the configuration of the curved portion 11 is shown in the upper right of FIG. 1, for example, a request point 15 is provided in front of the curved portion 11, and when the transport carriage passes this point, the travel permission of the curved portion 11 is given to the zone controller 30. The zone controller gives the travel permission to the exit point 16 of the curved portion 11 in a lump, and when the carriage passes the unlock point 17, the zone controller 30 reports that fact to the zone controller. The lock to the unit 11 is released. The transport carriage may request the zone controller to unlock instead of the passage report.

  The transport cart system 2 is controlled by a plurality of transport cart controllers 26, and the boundary of which transport cart controller manages is the transport cart controller boundary 18. Further, the boundary between which zone controllers are managed is the boundary 19 between the zone controllers.

  Reference numeral 20 denotes a backbone LAN. Reference numeral 22 denotes a physical distribution controller that manages the transport cart controller 26 and the like, communicates with a host controller 24 (not shown), accepts a transport request, and reports a transport result. An inter-zone LAN 28 is connected to the transport cart controller 26 to communicate between the plurality of zone controllers 30 and the transport cart controller 26.

  FIG. 2 shows the control of branching and merging near the shortcut 7. In the figure, 32 is a return path, the transport carriage 36 is one way from left to right, 34 is a forward path, and the transport carriage 36 is one way from right to left. And it branches to the shortcut 7 in the branch part 10, returns to the return path 32 in the junction part 8, and becomes an intersection substantially. For example, an anti-collision sensor 38 using optical, infrared, or ultrasonic waves is provided in front of the transport carriage 36 to check whether there is another preceding carriage in the range up to the collision prevention limit 39. . The collision prevention limit 39 is an inter-vehicle distance necessary to prevent a collision with the preceding carriage that is stopped. When another conveyance carriage is detected within the range up to the collision prevention limit 39, the collision prevention limit 39 is decelerated or stopped. To prevent collisions.

  The conveyance carriage 36 uses the collision prevention sensor 38 to control traveling except for the set sections such as the branching section 10 and the merging section 8. As a result, the communication amount with the zone controller 30 can be significantly reduced. The range occupied by is the length of the transport carriage 36 plus the collision prevention limit, and the transport efficiency is improved.

  When the transport carriage 36 passes through the junction 8, for example, when passing the request points 40 and 41 in front of it, the zone controller 30 is requested to permit travel. In the range of travel permission to be obtained, for example, portions of points necessary for passing through the junction 8 are collectively requested. When requesting on the return path 32, the travel permission to the points P1 to P4 is requested, and when requesting from the shortcut 7, the travel permission to the points P5, P3, P4 is requested. On the other hand, the zone controller 30 may permit travel for the requested section in a lump, or may grant travel permission only to a portion that can be permitted to travel. When the transport carriage 36 passes through each point, the travel permission is canceled for each point that has been passed, and travel permission for other transport carts is made possible. When the branching unit 10 is branched, the transport carriage 36 requests travel permission at a request point 42 in front of it, for example, travel permission from travel points P6 to P8 is collectively requested. On the other hand, the zone controller 30 permits traveling within a range where travel permission is possible, and the transport carriage 36 reports the fact to the zone controller 30 for each point that has passed and cancels the travel permission for each point. Alternatively, the position is reported every time the position recognition point 44 is passed, not every time the point is passed. When a position recognition point is provided in the set section, it is possible to confirm evacuation from the set section by reporting the passage of the position recognition point. For these reasons, the collision between the request point and the unlock point can be reliably prevented by the collision prevention sensor and the point lock.

  FIG. 3 shows an algorithm for collision prevention control in the embodiment. The transport carriage requests travel permission when passing the request point, and is controlled by a collision prevention sensor in other sections. When passing the request point, the controller is requested to allow the set section to travel, and the controller checks whether the requested section is locked. If it is not locked, the permitted section is locked, the travel permission is given to the transport carriage, and the transport carriage travels in the permitted section. The unit of the section permitted here may be the whole set section or may be one to a plurality of points in the set section. When travel permission is not obtained, the transport carriage decelerates in a predetermined pattern so as to stop before entering the set section. When the transport cart travels at the permitted point or passes the position recognition point next to the set section, the controller reports that fact and the controller unlocks the section that has already traveled.

  FIG. 4 shows travel control at the junction 8 and the branch 10 in the modification. 2 and 3 are the same as those shown in FIGS. 2 and 3, except that only one point of the point P9 of the merging unit 8 and the point P10 of the branching unit 10 is subject to exclusive control, and the section in which exclusive control is performed is minimized. . In addition, an unlock point 46 is provided on the exit side of the junction 8 and an unlock point 48 is provided on the exit side of the branching unit 10. When the transport carriage 36 passes these points, the fact is reported to the zone controller 30. The zone controller 30 monitors the position of the transport carriage by these signals and a signal indicating that the position recognition point in FIG. 3 has been passed, and unlocks the branching units 8 and 10. As a result, the section in which the exclusive control is performed at the junction 8 or the branching section 10 is the shortest, the communication amount between the zone controller 30 and the transport carriage 36 is reduced, and the wide section is not locked, so that the transport efficiency is increased.

  FIG. 5 shows a speed pattern of the request points at the junction 8 and the branch 10. In this case, when the travel permission is received from the zone controller 30 within the normal delay time, the request point can be traveled without decelerating the junction 8 and the branching section 10 as in the case of the solid line speed pattern. When the travel permission is not obtained within the delay time, it is as close as possible to the merging portion 8 and the branching portion 10 as long as it can stop before the branching portion 10 and the merging portion 8 by the speed pattern of the chain line. When the position recognition unit confirms that there is no other transport carriage at the junction 8 or the branching unit 10, the travel permission is obtained, and the vehicle can pass through these sections without decelerating. When travel permission cannot be obtained, the vehicle decelerates in a predetermined pattern so as to stop before entering the junction 8 or the branch 10.

  FIG. 6 shows communication between the zone controller 30 and the transport carriage 36 in the embodiment. An appropriate position sensor 50 is provided on the transport carriage 36 to detect a mark 52 (a mark of a position recognition point) made up of an optical mark, a communication terminal, and the like to recognize the position. When a communication terminal is used as the mark, the position is communicated to the position sensor 50 from the communication terminal side. The transport carriage 36 recognizes the current position by adding the travel distance obtained from the rotational speed of the travel wheel to the position thus obtained, and passes the unlock point each time the mark 52 is detected, for example. Each time, the current position is reported to the position recognition unit 54 of the zone controller 30. As a result, the zone controller 30 monitors the current position of each transport carriage 36.

  The travel permission unit 55 permits travel to the transport carriage 36 and locks other transport carts associated therewith with respect to set sections such as a junction, a branching section, a curved section, a station overcrowded section, and a maintenance section. Permission to travel is given by priority in the order of reception of the travel permission request, for example, so that the transport carriage does not request travel permission until the request point is reached, for example, to prevent requesting travel permission from a distance in the set section To do. Then, the position recognition unit 54 detects that the transport carriage has left the set section and releases the lock.

  By the way, after assigning a travel command to a transport cart, it may be necessary to cancel the transport command due to a request from a host controller or the like. If the carriage is attached with a travel permission for the set section to execute the transport command, the set section remains locked unless the permission is canceled. In this case, it is preferable that the transport cart requests the zone controller to cancel the travel permission, and the zone controller permits the cancellation. In addition to this, when a travel failure occurs in the set section, a request for canceling the travel permission may be requested from the zone controller to the transport cart that has given the travel permission, and the cancel permission may be received from the transport cart. preferable. A cancel processing unit 56 performs these processes.

FIG. 7 shows a format of a communication statement 60 from the zone controller to the conveyance carriage and a communication statement 62 from the conveyance carriage to the zone controller. The communication statement 60 describes the ID number of the transport carriage and other ID data, the type of command such as a travel permission request and a transport command, and data describing details of each command. In the case of the communication statement 62, in addition to the machine number and other ID data, the command type, the status report such as the error of the carriage, and the command details and the status report details are described. The communication texts 60 and 62 have two flags, 1 bit for cancel request and 1 bit for cancel permission. When these flags are set, the content of the communication text is a cancel request for travel permission or the like, and permission for cancellation. . In the case of a travel permission cancellation request and a cancellation permission for the cancellation request, the message format itself is the same as the travel permission request and the travel permission, and the points for requesting the travel permission or permitting the travel are included in the data. Describe in. In the communication texts 60 and 62, the cancel request bit and the cancel permission bit are provided. However, these may be described in the data, and the data expression itself is arbitrary.

Block diagram of the transport cart system of the embodiment The figure which shows the layout of the vicinity of the junction in the embodiment The flowchart which shows the collision prevention algorithm in an Example The figure which shows the layout of the vicinity of the merge part in the modification The figure which shows the traveling speed pattern near the junction part (intersection) in a modification The figure which shows the structure of the zone controller in an Example, and a conveyance trolley | bogie The figure which shows the communication format between the zone controller and conveyance trolley | bogie used in the Example

Explanation of symbols

2 Carriage system 4 Interbay route 6 Intrabay route 7 Shortcut 8 Junction section 10 Branch section 11 Curve section 12 Station congestion section 13 Maintenance section 15 Required points
16 Exit point 17 Unlock point 18 Boundary between transport carriage controllers 19 Boundary between zone controllers 20 Core LAN
22 Logistics controller 24 Host controller 26 Carriage truck controller 28 Interzone LAN
30 Zone controller 32 Return path 34 Outward path 36 Carriage truck 38 Collision prevention sensor 39 Collision prevention limit 40-42 Request point 44 Position recognition point 46, 48 Unlock point 50 Position sensor 52 Mark 54 Position recognition part 55 Travel permission part 56 Cancel processing part 60,62 Message P1-P10 Points

Claims (1)

The controller from the transport carriage, requesting travel permission of the section on the travel route, the controller permits the travel to the requested section, the conveyance carriage system for locking the section to the other conveying carriage,
In a station overcrowded section where stations are arranged at a distance narrower than the collision prevention limit, which is an inter-vehicle distance required to prevent a collision with at least a preceding transport carriage that is stopped, the traveling of the station overcrowded section When passing the request point provided on the front side of the direction , request permission to travel from the transport carriage to the controller,
The transport cart is provided with a collision prevention sensor and a position sensor, and each transport cart travels by monitoring the preceding transport cart with the collision prevention sensor except for a section that requires permission of travel from the transport cart to the controller. Report the position of the trolley to the controller,
When the controller confirms that the requested section is not locked and there are no interfering carriages , the controller permits the carriage that has requested permission to travel , and sets the sections permitted to travel to other sections . Do not allow other transport carts to run by locking the transport cart,
The conveyance carriage system is characterized in that the conveyance carriage reports to the controller that the vehicle has passed the section permitted to travel, and the controller releases the lock based on the report.

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