Integrated locking control and status indicator for manually operated railway switch stand

Abstract

The invention relates to a device to be integrated with to a manual switch stand, particularly for use in dark territory. The device secures the spindle of the switch stand against rotation, thereby preventing authorized throwing of the switches. The device also contains sensors that will clearly indicate to an external observer both the position of the switch points and the locked or unlocked status of the switch stand. A particular sequence of steps must be taken before an operator will be able to unlock the switch stand and throw the switch, and further steps are required before he can secure the switch stand and remove his key. The switch stand must therefore be left in a locked state, and it continuously indicates the status of the switch stand to a remote monitor.

Description

FIELD OF THE INVENTION[0001]This invention relates to a mechanism to provide a definite indication of the position of the switch controlled by a switch stand and to secure the stand against unauthorized switching, and is particularly applicable for stands used in dark territory.BACKGROUND OF THE INVENTION[0002]A railroad switch includes moveable switch points (sometimes called blades) that direct the wheels onto the appropriate track. The switch points are driven from a first position, to direct the train onto one track, to a second position, to direct the train onto another track, by a power operated switch machine, or by a manually operated switch stand. The points are locked in one position until required to be switched back to the other position. Rail terminology commonly refers to the switch point position for the track most frequently used as the “normal” position, and the position for the track less frequently used as the “reverse” position.[0003]A power operated switch machi...

AI Technical Summary

Benefits of technology

[0020]The locking control and status indicator prevents human error from compromising the safety of manually operated railway switches. It requires employees operating a switch stand to leave the stand in a locked state, and it continuously indicates the status of the switch stand (unlocked, locked in normal, or locked in reverse) through an external notification device to a remote monitor.

Problems solved by technology

The lock handle must be physically disengaged (unlocked) before the switch points can be moved, but the handle cannot be disengaged until the key is turned.

Further, once the key is inserted properly it is retained within the device and can only be removed once the locking handle has been returned to an engaged (locked) position, presumably after the switch points have been moved to the desired position.

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