Abstract: A pedestrian push button assembly for activating a signal generator to generate a signal at a street crosswalk. The pedestrian push button assembly has a rigid frame having a piezoelectric material of a solid state switch positioned across a central aperture, and an elastic sealing ring positioned in a groove surrounding the piezoelectric material. A button is secured to the rigid frame such that (1) a seal contact portion of the button sealably rests against the elastic sealing ring, (2) a very small space separates an abutment surface of the button and a stopper surface of the rigid frame, and (3) an elastic pressure portion of the button contacts the piezoelectric material. When operated, the elastic sealing ring is sufficiently biased to urge the elastic pressure portion against the piezoelectric material to generate a signal pulse.

Abstract: An accessible pedestrian signal system to assist visually impaired persons to cross a signal controlled intersection. The signal system has a push button which is pressed by the pedestrian. Circuitry is provided to vibrate the push button when the signal system is programmed to send a signal that it is time to cross the intersection. Preferably, the push button is mounted on a flexible diaphragm and a vibrating movement is transmitted to the inner surface of the diaphragm when it is desired to vibrate the push button. Preferably, the pressing of the button flexes a piezo-electric member which has an output to the circuitry of the signal system.