Automatic control system for railroad interlocking

Claim 2

A control arrangement for automatically alternating the passage of trains from two converging tracks through a track switch into a single track, comprising in combination, a. a first and a second approach relay coupled for registering the occupancy of the one or the other converging track, respectively, by an approaching train, b. train detector means coupled for detecting a train occupying a prefixed interlocking area where said tracks converge through said track switch into said single track, c. an indication means controlled by said switch for registering the established route condition, d. a sequencing means operable to a first and a second condition corresponding to one and the other converging tracks, respectively, e. route selection means controlled by said first and second approach relays and by said sequencing means and coupled for enabling the preparation of a route from one or the other converging track as an approaching train is detected in the corresponding track and said sequencing means operates to its corresponding condition, f. a reset circuit means controlled by said train detection means and said indication means and connected for resetting the approach relay, corresponding to the converging track on which a train, now detected in said prefixed interlocking area, approached, to a non-occupancy condition to register that train's passage into said single track, and g. an operating circuit means controlled by said first and second approach relays and connected for operating said sequencing means to a condition corresponding to a first approaching train registered occupying a particular converging track and to the other condition when passage of said first train into said single track is registered and a second approaching train is also registered occupying the other converging track.

Claim 3

A control arrangement as defined in claim 1 in which, said route selection means is also connected to said operating circuit means for inhibiting the operation of said sequencing means when a route is established.

Claim 4

A control arrangement as defined in claim 2 in which, a. said sequencing means is a two winding magnetic stick relay, and b. said operating circuit means comprises, 1. a first energizing circuit poled to operate said sequencing relay to its first condition and including a non-occupied position contact of the other converging track approach relay, one sequencing relay winding, and a circuit path controlled by said route selection means to be closed only when no route is established, 2. a second energizing circuit poled to operate said sequencing relay to its second condition and including an occupied condition contact of said other track approach relay, a non-occupied position contact of the one converging track approach relay, the sequencing relay other winding, and said closed route selection circuit path,

Claim 5

a first holding circuit for said one winding, poled to retain said sequencing relay in its first condition, including occupied position contacts of both approach relays, a first condition contact of said sequencing relay, and said closed route selection circuit path, and 4. a second holding for said other winding, poled to retain said sequencing relay in its second condition, including said occupied condition contacts of both approach relays, a second condition contact of said sequencing relay, and said closed route selection circuit path.

Claim 6

a first holding circuit for said one winding, poled to retain said sequencing relay in its first condition, including occupied position contacts of both approach relays, a first condition contact of said sequencing relay, and said closed route selection circuit path, and 4. a second holding for said other winding, poled to retain said sequencing relay in its second condition, including said occupied condition contacts of both approach relays, a second condition contact of said sequencing relay, and said closed route selection circuit path.

Claim 7

A control arrangement as defined in claim 3 in which, said first energizing circuit further includes in series an occupied position contact of said one track approach relay to enable said sequencing relay to hold in its existing position when both converging tracks are non-occupied.

Claim 8

In an automatic control system for a railroad interlocking, through which trains converge from two approach tracks through a track switch onto a single track, an arrangement for automatically alternating the movement of trains from the approach tracks, comprising in combination, a. a first and a second approach detection relay, each coupled for detecting the occupancy of the one and the other approach track, respectively, by an approaching train, b. a detector relay coupled to the rails within said interlocking limits and responsive to the passage of a train for registering the occupancy of the switch section, c. a switch position indicator coupled for indicating the position of the track switch selectively joining the approach tracks to said single track, d. a reset circuit network controlled by said detector relay and said switch position indicator and connected for selectively actuating each approach detection relay to a non-occupancy position when a train from the corresponding approach track occupies the switch section, e. a sequencing relay operable between a first and a second position in accordance with the actuating energy applied, f. route control means controlled by said approach detection relays and by said sequencing relay for alternately initiating the establishment of routes from each track when approaching trains are successively detected and said sequencing relay alternately operates between its first and second positions, each route being finally established when a preceding train completes its passage into said single track, and g. a control circuit network controlled by said approach detection relays and said route control means and connected for operating said sequencing relay alternately between its first and second positions when trains are successively detected in each approach track, said approach detection relays are reset by passage of each train through said interlocking limits, and the existing established route is cancelled.

Claim 9

In an automatic control system for a railroad interlocking, through which trains converge from two approach tracks through a track switch onto a single track, an arrangement for automatically alternating the movement of trains from the approach tracks, comprising in combination, a. a first and a second approach detection relay, each coupled for detecting the occupancy of the one and the other approach track, respectively, by an approaching train, b. a detector relay coupled to the rails within said interlocking limits and responsive to the passage of a train for registering the occupancy of the switch section, c. a switch position indicator coupled for indicating the position of the track switch selectively joining the approach tracks to said single track, d. a reset circuit network controlled by said detector relay and said switch position indicator and connected for selectively actuating each approach detection relay to a non-occupancy position when a train from the corresponding approach track occupies the switch section, e. a sequencing relay operable between a first and a second position in accordance with the actuating energy applied, f. route control means controlled by said approach detection relays and by said sequencing relay for alternately initiating the establishment of routes from each track when approaching trains are successively detected and said sequencing relay alternately operates between its first and second positions, each route being finally established when a preceding train completes its passage into said single track, and g. a control circuit network controlled by said approach detection relays and said route control means and connected for operating said sequencing relay alternately between its first and second positions when trains are successively detected in each approach track, said approach detection relays are reset by passage of each train through said interlocking limits, and the existing established route is cancelled.

Claim 10

A control system arrangement as defined in claim 5 in which said route control means comprises, a. a first and a second route relay associated with the one and the other approach track, respectively, and coupled for initiating when activated the establishment of a route from the associated track into said single track, and b. an energizing circuit for each route relay including, 1. a contact of said sequencing relay closed when the sequencing relay position corresponds to the approach track associated with that route relay, and 2. a contact closed when the corresponding approach relay detects a train occupying that approach track.