Abstract: A light signal provides fixed focus and the ability to service the device solely from the rear. This light signal comprises a housing having a rear entry for desired maintenance and an immovable front wall, the lens mount containing a lens unit that is removable secured to an inside surface of the immovable front wall of the housing. Each lens mount includes a fixed focusing means having a receptacle for operative receipt of a light means, wherein the fixed focusing means is positioned at the end of the lens mount nearest an inner lens; whereby the focus of the light means is fixed relative to the lens unit.

Abstract: A railway signaling relay for use in vital circuits has a high percentage release (ratio of drop away current to pickup current between 70% and 80%) by arrangement of contact springs and their associated pressure and stop plates which provide trapped pressure in the contact springs affording the high percentage release characteristic without modification of the electrical or basic mechanical configuration of the relay and retaining its vital characteristics.

Abstract: An improved railroad crossing signal includes a deep dish parabolic reflector and an essentially flat plastic lens angled forward at the top relative to the axis of the reflector. The lens includes prism elements for laterally dispersing parallel light from the reflector more toward the crossing highway at near and far distances than toward the adjacent land. The lens also includes prism elements for vertically dispersing a portion of the light to produce uniform brightness before the signal.