Car retarder control system

Claim 2

In a car retarder control system for a railway classification yard having a multi-position car retarder operable to different braking positions as each cut traverses said retarder for adjusting the speed at which cuts being classified couple on their assigned storage tracks, by reducing the speed of the cut from its entering velocity to a preselected exit velocity, the combination of: means responsive to the velocity of said cut when entering said retarder and to the preselected exit velocity for said cut for providing a manifestation representative of each braking force to be exerted by the retarder on each cut at each instant of its travel through the retarder to reduce its velocity to said preselected exit velocity at the exit end of the retarder, means for providing a manifestation related to the position of each cut as it passes through said retarder, and means responsive to said first recited means and said second recited means for varying the braking force exerted on each cut by said retarder as it passes through the retarder to reduce its velocity to said preselected exit velocity at the exit end of the retarder.

Claim 3

The retarder control system of claim 1 wherein the retarder is of the type which is operable to a plurality of discrete braking positions, said first named means computing, for each cut, the length of retarder required to reduce the speed of said cut to said preselected exit velocity at the exit end of said retarder in response to the application of light braking force by said retarder, said means controlling said retarder to apply a braking force greater than light only when said computed retarder length exceeds the length of said retarder.

Claim 4

Apparatus for controlling a discrete position retarder in a railroad classification yard in order to control the coupling speed of a cut when it reaches its destination track and couples to cars preceding it, comprising, means for determining the required length of retarder to decreAse the velocity of a cut as it enters the retarder to a preselected exit velocity with light braking only, means for comparing said previously computed length with the effective length of said retarder, means for storing the results if the required length is less than or equal to the effective length, and control means responsive to said means for storing to control said retarder in accordance with said stored results.

Claim 5

Apparatus for controlling a discrete position retarder in a railroad classification yard in order to control the coupling speed of a cut when it reaches its destination track and couples to cars preceding it, comprising, means for determining the required length of retarder to decreAse the velocity of a cut as it enters the retarder to a preselected exit velocity with light braking only, means for comparing said previously computed length with the effective length of said retarder, means for storing the results if the required length is less than or equal to the effective length, and control means responsive to said means for storing to control said retarder in accordance with said stored results.

Claim 6

The apparatus of claim 3 which further comprises, means for selecting, if said required length is greater than said actual length, a point intermediate the entrance and exit of said retarder and selecting a velocity for said cut which is intermediate the entrance and exit velocity, means for computing the required retarder length to decrease the velocity of the cut from said selected velocity to a preselected exit velocity with light braking only, means for comparing said last previously computed length with the length of said retarder from said intermediate point to said exit end, and means for transmitting the results, if the required length is less than or equal to the actual length, to said means for storing.

Claim 7

The apparatus of claim 4 which further comprises, means for incrementing the location of said intermediate point if the last computed length is greater than the length of said retarder from said intermediate point to said exit end and decrementing said selected velocity for said cut from said last selected velocity, means for determining the required length of said retarder to decrease said selected velocity of said cut to a preselected exit velocity with light braking only, means for comparing said previously computed length with the length of said retarder from said last selected intermediate point to the exit of said retarder, and means for transmitting the results, is the last computed length is less than or equal to the length of said retarder from said last selected intermediate point to the exit end, to said means for storing.

Claim 8

The apparatus of claim 5 which further includes means for determining when the distance from said intermediate selected point to the entrance of said retarder is equal to or greater than the length of said retarder, means responsive to said last named means for determining the required length of retarder to decrease the velocity of said cut as it enters the retarder to a preselected exit velocity with higher braking only, means for comparing said previously computed length with the effective length of said retarder, and means for transmitting the results, if the required length is less than or equal to the effective length, to said means for storing.

Claim 11

The method of claim 7 which further comprises, selecting, if the necessary length is greater than the length of retarder, a point intermediate the entrance and exit of said retarder and selecting a velocity for said cut at that point which is intermediate the entrance and exit velocity, computing the required retarder length to decrease the velocity of the cut from the selected velocity to the preselected exit velocity with light braking, comparing the last previously computed length with the retarder length from said selected point to the exit end, and computing and storing the elaspsed time and distance covered in reducing the velocity only if said computed length is less than or equal to the retarder length from said selected point to the exit end.

Claim 12

The method of claim 8 which further includes the steps of, incrementing the location of said selected point as measured from the entrance end and decrementing the sleected velocity if the computed length exceeds the length of said retarder from selected point to the exit end, computing the required length of retarder to decrease said selected velocity to said preselected exit velocity with light braking only, comparing said computed length with the length of said retarder from said selected point to the exit end, computing and storing the time elapsed and distance covered in reducing the velocity to said preselected exit velocity if the computed length is less than or equal to the length of retarder from said intermediate point to the exit end.

Claim 13

The method of claim 9 which further includes the steps of, determining where the distance from said entrance end to the incremented intermediate point is equal to or greater than the length of the retarder, computing required length of retarder to decrease the velocity of said cut as it enters the retarder to a preselected exit velocity with higher braking, comparing the previously computed length with the length of the retarder, computing and storing the elapsed time and distance to decrease the velocity to the exit velocity if said computed length is less than or equal to the length of said retarder.

Claim 14

The method of claim 8 which further includes the steps of, defining the length of the retarder as the distance between the entrance of said retarder and said intermediate point defining said preselected exit velocity as said selected velocity, computing the retarder length necessary to decrease the entrance velocity of the exit to said preselected exit velocity at higher braking, comparing said last computed length with the length of the retarder, computing and storing the time elapsed and distance covered in reducing the velocity to the preselected exit velocity if the computed length is less than or equal to the length of the retarder.

Claim 15

Apparatus for controlling a retarder to decelerate a cut passing therethrough to a preselected exit velocity comprising, first means for determining if light braking, only, is sufficient to decelerate said cut to said preselected exit velocity and for computing the extent of said light braking if light braking, only, is sufficient, second means, responsive to said first means, for determining, if said light braking only, is insufficient, the extent, if any, of light braking to decelerate said cut to said preselected exit velocity with braking force transitions along a desired velocity-distance profile and for also determining an intermediate velocity of said cut at said braking force transition, third means, responsive to said second means, for determining a minimum braking level, above light braking, and the extent thereof required, to decelerate said cut to said intermediate velocity with braking force transitions along said desired velocity-distance profile, fourth means, responsive to said first, second, and third means for storing parameters associated with the respective braking levels determined by said first, second, and third means, and control means, responsive to said fourth means, to control said multi-position retarder to its various braking positions to the extent stored by said fourth means.

Claim 16

Apparatus for controlling a retarder to decelerate a cut passing therethrough to a preselected exit velocity comprising, first means for determining if light braking, only, is sufficient to decelerate said cut to said preselected exit velocity and for computing the extent of said light braking if light braking, only, is sufficient, second means, responsive to said first means, for determining, if said light braking only, is insufficient, the extent, if any, of light braking to decelerate said cut to said preselected exit velocity with braking force transitions along a desired velocity-distance profile and for also determining an intermediate velocity of said cut at said braking force transition, third means, responsive to said second means, for determining a minimum braking level, above light braking, and the extent thereof required, to decelerate said cut to said intermediate velocity with braking force transitions along said desired velocity-distance profile, fourth means, responsive to said first, second, and third means for storing parameters associated with the respective braking levels determined by said first, second, and third means, and control means, responsive to said fourth means, to control said multi-position retarder to its various braking positions to the extent stored by said fourth means.