Abstract: A vandal resistant light signal unit consisting of a modular integrated circuit arrangement having an insulative circuit board, which has a first broad area layer of conductive material on one side of the circuit board and a second broad area layer on an opposite side of the circuit board. The first layer defines a positive energy plane and the second a negative energy plane. Also, the unit has a plurality of independent series circuits connected in parallel to respective spaced points or nodes on the oppositely located layers of conductive material. Moreover, the broad area layers are connected to opposite sides of a power supply, and these layers constitute an arrangement for resisting vandalism occasioned by projectiles directed at said light signal unit.

Abstract: There is provided an electric motor driven switch machine for positioning a railroad track at a switching point having rail point detection and indication mechanism. In particular, the detection and indication mechanism has a latch out mechanism that identifies a latch out condition when the railroad tracks are not at, or near, their proper positions before or after switching the railroad tracks. The detection and indication mechanism includes a four bar linkage which comprises a point detector bar, two cam followers, and a link arm assembly. The cam followers, supported in part by the link arm assembly, are connected to two point detector switches, so that the switch machine is operating when either one of these switches is closed or the railroad tracks are being switched.

Abstract: Apparatus for operating railroad switches, including operation in the trailing mode, and a switch machine having a throw bar and throw rod for enabling the throwing of switch points into selected positions so as to control the switching of rolling stock. A trailing device, including a trailing rod portion of the throw rod, is coupled to the throw bar, said device including an arrangement responsive to a wrong direction load impressed on said switch points so as to move said throw rod, for enabling non-damaging movement of said throw rod.

Abstract: There is provided a cam bar of a railroad track switch machine for locking a lock bar at a particular position. Specifically, a cam bar latch interconnects a locking section, for interlocking with the lock bar, to a positioning section, for controlling the position of the locking section. For normal operations, the cam bar latch holds the two sections together. For abnormal conditions, when the cam bar is not able to lock the lock bar into position, the cam bar latch allows the two sections of the cam bar to separate and reconnect interchangeably. Thus, the positioning section may continue to move freely regardless of whether the lock bar is locked or not, and yet, control the position of the locking section when a normal condition returns. Also, the cam bar prevents an indicating means of the switch machine from indicating a "safe condition" when the two sections are separated, i.e., when an abnormal condition exists.

Abstract: There is provided an improved hand throw device of an electric motor driven switch machine having a ratchet mechanism that permits torque to be applied to the hand throw device in either a clockwise or counter-clockwise direction as desired by an operator. The ratchet mechanism is a self contained module that can be easily installed to either side of the switch machine. The ratchet mechanism also permits the operator to assume a favorable position for application of force to the hand throw device with minimum stress and strain to his or her body. In addition, the ratchet mechanism has a gear system that provides a 2 to 1 mechanical advantage so that less torque is required for movement of the hand throw device.