Monitoring of track-type conveyor system

{
  "publication_number": "US5236156A",
  "country": "US",
  "kind": "A",
  "title": "Monitoring of track-type conveyor system",
  "abstract": "A conveyor system has a track network including a main track, a plurality of branch tracks, and respective intersections at which the main track joins the branch tracks. Respective stations at the branch tracks are each associated with a respective target code. A plurality of trucks displaceable along the track network are shuntable by switches at the intersections from the main track into the branch tracks. Each truck is provided with an array of elements settable to correspond to any of the target codes and respective target-code readers associated with the switches read the target codes of the trucks. Controllers connected between the readers and the respective switches direct the trucks to the stations corresponding to the target codes of the trucks. A monitoring system comprises a permanent identification code on each of the trucks associated with the respective truck and not with the station to which the truck is addressed and identification-code readers along the track network responsive to the identification codes on the trucks. A central computer connected to the readers is responsive to the identification-code readers for monitoring positions of the trucks along the track network. An encoder connected to the central computer is disposed along the network for, in response to the central computer, reprogramming a target code of selected trucks passing the encoder.",
  "claims": [
    "1. A conveyor system comprising: a track network including a main track, branch tracks, a plurality of stations on the branch tracks each associated with a respective target code, and intersections at which the branch tracks join the main track; a plurality of tracks displaceable along the track network; means on each truck including a respective array of elements settable to correspond to any of the target codes; respective switches at the intersections operable to shunt the tracks from the main track to the respective branch track; means including respective readers associated with the switches for reading the target codes of the trucks at the respective switches; respective control means connected between the readers and the respective switches for operating the switches to direct the trucks to the stations corresponding to the target codes of the trucks; an identification code on each of the trucks associated with the respective truck and not with the station to which the truck is addressed; identification-code readers at the target-code readers responsive to the identification codes on the trucks; a central computer connected to the identification-code readers for monitoring positions of the trucks along the track network; and an encoder connected to the central computer and disposed along the network for, in response to the central computer, reprogramming target codes of selected trucks passing the encoder.",
    "2. The conveyor defined in claim 1 wherein at least one further reader is provided along the track and has an identification-code reader and a target-code reader, the further reader being connected with the central computer.",
    "3. The conveyor defined in claim 1 wherein the readers comprise microprocessors.",
    "4. The conveyor defined in claim 1 wherein the readers receive signals from the central computer for controlling the switches.",
    "5. The conveyor defined in claim 1, further comprising a screen display connected to the central computer.",
    "6. The conveyor defined in claim 1, further comprising a printer connected to the central computer.",
    "7. In a conveyor system comprising: a track network including a main track, a plurality of branch tracks, and respective intersections at which the main track joins the branch tracks; respective stations at the branch tracks, each station being associated with a respective target code; respective switches at the intersections; a plurality of trucks displaceable along the track network and shuntable by the switches from the main track into the branch tracks; means on each truck including an array of elements settable to correspond to any of the target codes; means including respective target-code readers associated with the switches for reading the target codes of the trucks; respective means connected between the readers and the respective switches for directing the trucks to the stations corresponding to the target codes of the trucks; a monitoring system comprising: a permanent identification code on each of the trucks associated with the respective truck and not with the station to which the truck is addressed; identification-code readers along the track network responsive to the identification codes on the trucks; a central computer connected to the readers and responsive to the identification-code readers thereof for monitoring positions of the trucks along the track network; and an encoder connected to the central computer and disposed along the network for, in response to the central computer, reprogramming target codes of selected trucks passing the encoder.",
    "8. A method of operating a conveyor system comprising: a track network including a main track, a plurality of branch tracks, and respective intersections at which the main track joins the branch tracks; respective stations at the branch tracks, each station being associated with a respective target code; respective switches at the intersections; a plurality of trucks displaceable along the track network and shuntable by the switches from the main track into the branch tracks; means on each truck including a array of elements settable to correspond to any of the target codes; means including respective readers associated with the switches for reading the target codes of the trucks; respective means connected between the readers and the respective switches for directing the trucks to the stations corresponding to the target codes of the trucks; the method comprising the steps of: providing each truck with a permanent identification code associated with the respective truck and not with the station to which the truck is addressed; reading the identification codes of the trucks at identification stations along the track network; centrally tracking the positions of the trucks by monitoring the identification codes read at the identification stations and determining when a truck is unable to reach its destination; resetting the target code of a truck unable to reach its destination to correspond to the code of a station serving as accumulation station."
  ],
  "description_excerpt": "The present invention relates to a conveyor system where a plurality of cars are routed over a track network between a plurality of stations. More particularly this invention concerns a monitoring system for such a conveyor system.\n\nA standard conveyor of this type has track-guided trucks which travel along a track network provided with switch points at which the trucks can be shunted off to branch tracks, or to loading or unloading stations. Each track carries a target code that is set according to the intended destination of the truck and each switch point is provided with a device that can read these codes. When a reader determines based on the code of an arriving truck that this truck should be switched to a branch track or a station, it appropriately operates the respective switch. The network invariably includes at least one endless main track about which the trucks travel until they are picked off at a switch point. Such arrangements are described in U.S. Pat. Nos. 3,340,821 and 3,502,038. In such conveyors, the target codes consist of one or more electromagnets arranged on the conveyor truck and settable in binary fashion to form the desired destination code.\n\nSuch conveyor installations function well, however it is not possible to monitor the operation situation, for instance to establish whether a certain truck really reached its target station, according to the initial setting. Furthermore if, for instance, a destination code is set that corresponds to no existing destination, the respective truck will simply continue to move around the loop and, in effect, become lost.",
  "cpc": [
    "B65G 1/137",
    "B61L 23/005"
  ],
  "ipc": [
    "B61L 23/00",
    "B61L 27/04"
  ],
  "assignees": [
    "Buro Patent AG"
  ],
  "inventors": [
    "Rolf Zimmermann"
  ],
  "filing_date": "1992-03-30",
  "publication_date": "1993-08-17",
  "grant_date": "1993-08-17",
  "priority_date": "1988-10-20",
  "application_number": "US-85982192-A",
  "family_id": "27174604",
  "cited_by_count": 8,
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}