Patent ID: 8514090

Claim:
Dust level sensor arrangement mounted into a lid of a dust collection container in which dust, that descends from a dust separator positioned above said lid, accumulates, and the dust level sensor arrangement being sensitive to the level of an upper surface of the accumulated dust in the container to alert an operator when the dust has risen to a predetermined level beneath said lid, the arrangement comprising a sensor attached onto said lid generating radiation that is directed downward into the drum and is reflected off the upper surface of the accumulated dust, and providing an output signal that goes from one sense to another sense when the dust has reached said predetermined level, wherein said predetermined level is at a finite distance below said sensor such that said sensor output signal goes from said one sense to the other sense without the sensor actually touching the accumulated dust; and a strobe alarm that is coupled to said sensor and is triggered by the output signal of the sensor to generate a visible strobe alert signal when said accumulated dust has reached said predetermined level in the container.