Patent ID: 8813558

Claim:
A fluid detector for determining a presence of a fluid within a container having a wall with an outer surface and an inner surface, the fluid detector comprising: a sensor assembly that outputs a first ultrasonic signal in response to an input electrical signal, the sensor assembly including a sensor element and a lens with an upper portion and a lower portion; a generally cylindrical wall being integral with and extending outwardly from the outer surface of the wall of the container, the generally cylindrical wall defining a housing with a cylindrical central bore having a base surface adjacent the outer surface of the wall of the container; and wherein the sensor element is coupled to the upper portion of the lens so that, when the lens is disposed within the cylindrical central bore adjacent the base surface such that the lens is intermediate the sensor element and the wall, the lens focuses the first ultrasonic signal toward the wall so that the first ultrasonic signal enters the wall; and wherein the sensor assembly is disposed in a predetermined position adjacent the outer surface of the wall such that the sensor assembly receives a second ultrasonic signal from the wall that results from the first ultrasonic signal and that is affected in a predetermined manner by presence or absence of fluid at the inner surface of the wall, wherein the sensor element generates an output electrical signal corresponding to the second ultrasonic signal.