Centralized traffic control system for railroads

Claim 2

Centralized traffic control apparatus for governing from a central office a plurality of groups of track switches and signals disposed along a stretch of railway track and comprising, a plurality of switching means for designating a selected control for any track switch or signal in any selected group of said track switches and signals comprising a field station, indication storage means responsive to the conditions of said track switches and signals and also to the occupancy of the associated trackway at said field stations, electronic digital computer means including a central processing unit and means for storing a program which comprises a plurality of sub-routines each associated with a corresponding one of said field stations, means responsive to the designation of a particular field station as the intended recipient of a control for selecting the subroutine associated with said particular station from said program storage means and being further responsive to the designation of a particular track switch or signal at said particular field station for rendering effective the portion of the sub-routine associated with said particular track switch or signal, and means controlled by the portion of the program sub-routine rendered effective in response to the designation by said switch means of a selected control for a specific track switch or signal to interrogate on successive steps programmed addresses of said indication storage means to determine whether the conditions of all of the track switches and signals relevant to said preselected control are such as to render said control permissible, and means for transmitting only a permissible control as determined by said controlled means to the field station intended to receive that control.

Claim 3

The apparatus of claim 1 wherein said indication storage means comprises, a first indication file for temporarily storing the indications received from a field station and having a capacity to store the maximum number of indications contemplated to be received from any single field station, a second indication file for storing the indications representative of the conditions of all the devices at all the field stations controlled from said control office, an indication change file, means effective upon the receipt of any new indication from a particular field station for comparing the thus received indications with those stored for that station in said second indication file and for storing in said indication change file only those indications received from said particular field station which are different from those which are then stored in said second indication file, and means for altering the indications in said second indication file in accordance with the changed indications stored in said indication change file.

Claim 4

The apparatus of claim 1 wherein said indication storage means includes at least one cathode ray display tube, and means for graphically displaying on said cathode ray tube the indications for any said field station as stored in said indication storage means.

Claim 5

The apparatus of claim 3 which further includes a manually operable keyboard, means for storing for each field station the track layout at each of the field stations and also the location of the track switches and signals at each respective field station, means governed by said keyboard for displaying on said cathode ray tube the track layout and locations of track switches and wayside signals at any selected field station, said indication storage means controlling said cathode ray tube to provide a distinctive display in association with each graphical representation therein of a track switch or wayside signal in accordance with the then-existing condition of such switch or signal as then stored in said indication storage means.

Claim 6

Centralized traffic control apparatus for governing from a central office a plurality of field stations disposed along a stretch of railway track each comprising a group of track switches and signals, said apparatus comprising, a master control panel at the central office including a changeable display means for diagrammatically displaying the track layout at any selected field station, the locations of the track switches and signals at said selected field station, and for displaying also the operated conditions of said track switches and signals in the selected field station, said master control panel further including a plurality of manually operable switch means for designating a selected control for any switch or signal at a selected field station, indication storage means responsive to the conditions of said track switches and signals at said field station and to the occupancy of the associated trackway, control storage means responsive to the conditions of said manually operable switch means, program storage means for storing a predetermined program for each of said field stations which is responsive to the designation of a particular field station by said manually operable switch means to select the respective program for such designated field station, electronic computer means responsive jointly to the selected program of said program storage means, to the operated positions of said manually operable switch means, and to said indication storage means for determining on the basis of the then-existing conditions of the track switches and signals at selected field stations whether the then-designated control for said particular station is a permissible control, and means for transmitting a code from said central office to said particular field station representative of said permissible control.

Claim 7

Centralized traffic control apparatus for governing from a central office a plurality of field stations disposed along a stretch of railway track each comprising a group of track switches and signals, said apparatus comprising, a master control panel at the central office including a changeable display means for diagrammatically displaying the track layout at any selected field station, the locations of the track switches and signals at said selected field station, and for displaying also the operated conditions of said track switches and signals in the selected field station, said master control panel further including a plurality of manually operable switch means for designating a selected control for any switch or signal at a selected field station, indication storage means responsive to the conditions of said track switches and signals at said field station and to the occupancy of the associated trackway, control storage means responsive to the conditions of said manually operable switch means, program storage means for storing a predetermined program for each of said field stations which is responsive to the designation of a particular field station by said manually operable switch means to select the respective program for such designated field station, electronic computer means responsive jointly to the selected program of said program storage means, to the operated positions of said manually operable switch means, and to said indication storage means for determining on the basis of the then-existing conditions of the track switches and signals at selected field stations whether the then-designated control for said particular station is a permissible control, and means for transmitting a code from said central office to said particular field station representative of said permissible control.

Claim 8

Centralized traffic control apparatus for governing from a central office a plurality of groups of track switches and signals disposed along a stretch of railway track each of which groups comprises a respective field station, said apparatus comprising, a master control panel at the central office including a changeable display means for diagrammatically displaying the track switches and signals at any selected one of said field stations and for displaying also the operated conditions of said track switches and signals as well as the occupancy of the associated trackway at the selected field station, said master control panel further including a plurality of manually operable switch means for designating a selected control for any switch or signal at the selected field station, indication storage means responsive to the conditions of said track switches and signals at said field stations and also the occupancy of the associated trackway, control storage means responsive to the conditions of said manually operable switch means and having at least one bit storage for each track switch or for each signal at each field station, means responsive to the designation of a new control by said manually operable switch means for controlling said display means to display the newly-designated control while concurrently indicating also that such newly-designated control has not yet become effective at the designated field station, program storage means for said field stations which is responsive to the designation of a particular field station by said manually operable switch means to select the respective program for such field station, electronic computer means responsive jointly to the selected program of said program storage means, to the operated positions of said manually operable switch means, and to said indication storage means for determining on the basis of the then-existing conditions of the track switches and signals at selected field stations whether then then-designated control For said particular station is a permissible control, means for transmitting a code from said central office to said particular field station representative of said permissible control, means for transmitting an indication code from each field station to said central office for storage in said indication storage means, and means responsive to the entry into said indication storage means of an indication code for said particular field station which differs from that previously stored therein for controlling said display means to display an indication representative of the operated conditions of said track switches and signals at said particular field station.

Claim 9

Centralized traffic control apparatus for governing from a central office a plurality of groups of track switches and signals disposed along a stretch of railway track each of which groups comprises a respective field station, said apparatus comprising, a master control panel at the central office including a changeable display means for diagrammatically displaying the track switches and signals at any selected one of said field stations and for displaying also the operated conditions of said track switches and signals as well as the occupancy of the associated trackway at the selected field station, said master control panel further including a plurality of manually operable switch means for designating a selected control for any switch or signal at the selected field station, indication storage means responsive to the conditions of said track switches and signals at said field stations and also the occupancy of the associated trackway, control storage means responsive to the conditions of said manually operable switch means and having at least one bit storage for each track switch or for each signal at each field station, means responsive to the designation of a new control by said manually operable switch means for controlling said display means to display the newly-designated control while concurrently indicating also that such newly-designated control has not yet become effective at the designated field station, program storage means for said field stations which is responsive to the designation of a particular field station by said manually operable switch means to select the respective program for such field station, electronic computer means responsive jointly to the selected program of said program storage means, to the operated positions of said manually operable switch means, and to said indication storage means for determining on the basis of the then-existing conditions of the track switches and signals at selected field stations whether then then-designated control For said particular station is a permissible control, means for transmitting a code from said central office to said particular field station representative of said permissible control, means for transmitting an indication code from each field station to said central office for storage in said indication storage means, and means responsive to the entry into said indication storage means of an indication code for said particular field station which differs from that previously stored therein for controlling said display means to display an indication representative of the operated conditions of said track switches and signals at said particular field station.

Claim 12

The method of claim 7 which further includes the steps of: receiving data from each of said field stations representative of the conditions of the track switches and signals at said field station and also of the occupancy conditions of associated track sections, comparing the received data with the already stored data in the memory to determine if there is a change in such data, and altering the data in the memory in accordance with the newly-received data only when the comparison step establishes that an indication change has occurred.

Claim 15

In the method of claim 9 which includes the further steps of: monitoring new indications received from said communication link related to said railroad portion, again determining, from those previously determined impermissible controls, if any are now permissible in light of said new indications, and again storing for transmission over said communication link only those of said previously impermissible controls which are now permissible.