SWITCH CONTROL ARRANGEMENT FOR RAILROAD CLASSIFICATION YARDS

• US 3,736,420 A
• Filed: 09/13/1971
• Issued: 05/29/1973
• Est. Priority Date: 09/13/1971
• Status: Expired due to Term

• Current Assignee: Union Switch & Signal, Inc. (Hitachi, Ltd.)
• Original Assignee: Elder J. Calvin, William B. Dufer
• Inventors: Elder, J. Calvin, Dufer, William B.
• Primary Examiner(s): Forlenza, Gerald M.
• Assistant Examiner(s): Libman, George H.
• Application Number:
  US05/179,728
• Time in Patent Office: 624 Days
• Field of Search: 246/77,182A,182AA,182AB 104/26
• US Class Current: 246/182.00A
• CPC Class Codes: B61L 17/00 Switching systems for classification yards

Abstract

The central data processor controlling the automatic switching system also compares the initial axle count, registered when a car enters the yard, with the axle count for that car from a wheel detector in the approach to each switch along the selected route. As long as the compared counts are not equal, the data processor holds energized an added detector relay. Back contacts of this relay interrupt the switch control circuit network to inhibit switch operation to the position selected for the next car, in the same manner as switch detector track circuit relay contacts are used. Thus the switch is locked against movement, not only when the associated track circuit is occupied but by lack of comparison between the axle counts if the track circuit is spanned, and full operating safety is maintained even with long cars. Blocking jacks for each storage track are provided in the track diagram on the yard control console. Insertion of a plug into a jack, to block further entry of cars in that track, activates a circuit network which bypasses and thus inhibits control of the key switch for that track by the data processor. Rather the key switch is positioned and held, overriding all other controls, to route all approaching cars away from the route to the blocked track or tracks.

Claims

1. A control arrangement for a track switch in a railroad classification yard, comprising in combination, a. a switch movement means operable to move said track switch between two opposite positions to establish a first or a second route for cars traversing said switch, b. an automatic control means for said yard for selecting a switch position to establish the desired route for each car scheduled to traverse said switch, 1. said automatic control means jointly controlled by the entry of a particular car into said yard and the passage of that car at said switch for detecting when that car has completed its passage of a preselected point at said switch. c. a position selection means controlled by said automatic control means and connected for controlling said switch movement means to move said track switch to the selected position for an approaching car, d. a first inhibit means jointly controlled by said automatic control means and by the movement of a car over said track switch and connected for interrupting the control of said switch movement means by said position selection means when a car is traversing said switch, and e. a second inhibit means operable to block a selected one of the two routes over said switch to car movement and connected when so operated for interrupting the control of said switch movement means by said position selection means to establish said blocked route.

2. A switch control arrangement as defined in claim 1 in which, said second inhibit means further controls said switch movement means for moving and holding said track switch in the position to establish the route other than said selected blocked route.

3. the associated blocking means to inhibit switch operation to establish a closed route, and

4. A switch control arrangement as defined in claim 3 which further includes, a. a track circuit means at said switch location controlling a track relay for detecting the presence of a car wheel and axle unit within preselectEd limits including said switch,

5. A switch control arrangement as defined in claim 2 in which said second inhibit means comprises, a. selector means for each route diverging from said switch, each normally occupying a first condition and manually operable to a second condition to selectively block entry of cars into the corresponding route, b. each selector means connected for interrupting control of said switch movement means by said position selection means and controlling said switch movement means to establish the other route over said switch.

6. A switch control arrangement as defined in claim 3 in which said second inhibit means comprises, a. selector means for each route diverging from said switch, each normally occupying a first condition and manually operable to a second condition to selectively block entry of cars into the corresponding route, b. each selector means connected for interrupting control of said switch movement means by said position selection means and controlling said switch movement means to establish the other route over said switch.

7. A switch control arrangement as defined in claim 6 in which said position selection means comprises a circuit network including, a. two principal circuit paths selectively controlled by said automatic control means for controlling said switch movement means to move said switch to the position corresponding to the desired route for an approaching car,

8. In a railroad classification yard control system, including a plurality of track switches to establish routes for cars to selected storage tracks, the combination comprising, a. automatic control means operable to receive selected car destinations and control said yard switches to successively establish a route to the selected storage track destination for each car entering said yard, b. initial detection means responsive to each car entering said yard and connected for registering in said automatic control means at least the axle count for such cars, c. track detection means at each switch for detecting cars occupying predetermined track limits at and including the corresponding switch and operable to a first or a second condition as said track limits are unoccupied or occupied, respectively, by a car, d. axle counting means located in the immediate approach to each switch and responsive to the passage of each car axle for registering a count of that axle in said automatic control means, e. said automatic control means being responsive to the reception of axle counts from each axle counting means for comparing the new count with the initially registered coUnt for that car to detect when that car completes its passage by the active axle counting means, f. count comparison detection means associated with each switch normally occupying a first condition and controlled by said automatic control means to a second condition during the comparison of the registered initial axle count for a car and the new axle count by the corresponding axle counting means when the compared counts are not equal, and g. operating means for each switch controlled by said automatic control means for positioning the associated switch to establish the selected route for an approaching car, h. said operating means further jointly controlled by both corresponding detection means for inhibiting the positioning of the associated switch to a new position when either of the corresponding detection means in in its second condition.

9. A yard control system as defined in claim 8 in which, a. each said track detection means is a track circuit including a track relay normally energized when the track within said limits at said associated switch is unoccupied and becoming deenergized when a car occupies the track within said limits, said track circuit being spannable by certain cars moving in said yard, b. each said count comparison detection means is a normally deenergized relay connected to be energized by said automatic control means when compared counts are not equal, and said combination further includes, c. a control circuit for each switch operating means including,

10. In a railroad classification yard control system, including a plurality of track switches to establish routes for cars to selected storage tracks, the combination comprising, a. automatic control means connected to receive preselected storage track destinations for cars entering said yard and operable for selecting successive switch positions to establish a route for each car to its preselected destination, b. operating means for each switch controlled by said automatic control means for positioning the associated switch to establish a route for an approaching car in accordance with its preselected destination, c. detection means at each switch location responsive to a car traversing the corresponding switch and connected for inhibiting the operation of that switch to establish a different route until the detected car clears the switch location, and d. blocking means for each storage track selectively operable to block entry of cars into the corresponding track, e. each blocking means connected to the operating means for a final switch to the corresponding storage track for inhibiting all other control of the final switch operating means and for holding said final switch in position to establish only a route leading away from the blocked storage track when that blocking means is in its blocking condition.

11. A yard control system as defined in claim 10 which further includes, a. manual control means for each switch operable when selectively actuated for manually selecting switch positions and connected for controlling the associated switch operating means to position that switch to the manually selected position, and in which, b. each blocking means includes a relay normally in a first position and selectively operable to a second position to block entry of cars into the corresponding storage track, c. each operating means includes a switch movement means for the associated track switch and a control circuit network therefor comprising,

12. A track switch control arrangement for a railroad classification yard, in which cuts of cars entering on a single track lead are selectively routed over the switches to a plurality of storage tracks, comprising in combination, a. switch movement means for each switch operable for positioning the associated switch to a first or a second position in accordance with the preselected route for each car cut traversing that switch, b. automatic control means for registering a preselected destination for each cut entering said yard and connected to select successive switch positions for each cut traversing the yard in accordance with the preselected destinations stored for the car cuts, c. initial cut detection means for measuring the parameters of each car cut entering said yard and connected to said automatic control means for storing at least the axle count parameter while the corresponding cut moves to its final destination, d. a detector track circuit at each switch for detecting the presence of cuts occupying the switch location within preestablished limits, said track circuits being spannable by certain cars at times included in said cuts, e. a wheel detector in approach to each switch responsive to the passage of each wheel and axle unit of cuts traversing the corresponding switch and connected to record that passage as an axle count in said automatic control means,