Train detection system operating in accordance with the axle-counting principle
AssigneeAlcatel
InventorsKarl U. Dobler, Helmut Uebel
Life of this patent
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Abstract
A train detection system is disclosed which works on the axle-counting principle and in which preprocessing units each containing a two-microprocessor system are associated with the individual detection points. Along the track, a major number of preprocessing units are connected with a central evaluation unit which interrogates the preprocessing units for stored counts on a cyclic basis. This interrogation is performed separately for each microprocessor of a preprocessing unit. In addition to containing counts, data telegrams transmitted to the evaluation unit include functional characters which make it possible to check the correct functioning of the detection points and preprocessing units at short intervals.
Claims5
In a train detection system for sections of track each defined by at least two detection points each of which is formed by at least two axle detectors staggered one relative to the other, arranged along the rails of the track and providing axle-presence signals:
- a central evaluation unit which indicates a particular track section as being occupied or unoccupied depending upon the number of axles counted at the associated detection points as axles entering the track section and as axles leaving the track section,
- a preprocessing unit provided in the immediate vicinity of each detection point and associated therewith, each preprocessing unit containing
- processing means for separate processing of the axle detector signals only from the associated detection point and accumulating a separate multi-bit count which is incremented each time an axle is detected as having passed the associated detection point in a first direction and which is decremented each time an axle is detected as having passed said associated detection point in a second direction, as well as
- a data transmitter-receiver for call-controlled transfer of the accumulated multi-bit count to the central evaluation unit, and
- call-up means associated with said central evaluation unit for cyclically calling up the counts stored by each of the preprocessing units.
A train detection system for sections of track which are defined by detection points each of which is formed by a pair of axle detectors staggered one relative to the other, arranged along the rails of the track and providing axle-presence signals, wherein a plurality of detection points is assigned to a central evaluation unit which indicates a track section as being occupied or unoccupied depending upon the number of axles counted at the associated detection points as axles entering the track section and as axles leaving the track section, characterized in that a preprocessing unit is provided in the immediate vicinity of each detection point and associated therewith, each preprocessing unit containing two microprocessors for separate, parallel processing and counting of the axle detector signals and buffering of the counts, as well as a data transmitter-receiver for call-controlled transfer of these counts to the central evaluation unit, and in that a comparison of the counts determined by the microprocessors of a preprocessing unit is performed in the central evaluation unit and further employment of these counts is prevented if the comparision shows in disagreement, further characterized in that in each preprocessing unit, each microprocessor has a check-pulse circuit associated with it which amplifies a check pulse outputted by the associated microprocessor in response to an instruction from the central evaluation unit and having a duration shorter than a predetermined minimum duration of the axle detector signals, and feeds the amplified check pulse to the axle detectors, in that in the axle detectors the check pulse generates a simulated axle count pulse having the duration of the check pulse, and in that the microprocessors output a special signal to the central evaluating unit when a simulated axle count pulse of this nature has been received.
In a train detection system for sections of track which are defined by detection points each of which is formed by at least two axle detectors staggered one relative to the other, arranged along the rails of the track and providing axle-presence signals:
- a central evaluation unit which indicates a track section as being occupied or unoccupied depending upon the number of axles counted at the associated detection points as axles entering the track section and as axles leaving the track section,
- a preprocessing unit provided in the immediate vicinity of each detection point and associated therewith, each preprocessing unit containing
- two processing means for separate, parallel processing of the axle detector signals and for accumulating two separate multi-bit counts each of which being incremented each time an axle is detected as having passed the associated detection point in a first direction and decremented each time an axle is detected as having passed said associated detection point in a second direction, as well as
- a data transmitter-receiver for call-controlled transfer of the multi-bit count accumulated by each of said two processing means to the central evaluation unit, and
- call-up means associated with said central evaluation unit for cyclically calling up the counts stored by each of the preprocessing units,
- wherein a comparison of the counts determined by the two processing means of a preprocessing unit is performed in the central evaluation unit and further employment of these counts is prevented if the comparison shows any disagreement.
Dependencies are inferred from the claim text.