A particle monitoring device located in a line carrying a moving fluid, as air, containing particles. The device has a particle sensing member providing audio signals that are in proportion to the amount of particles moving with the fluid. The sensing member is a flexible sheet member closing an open end of a connector housing having a chamber. Particles that hit the active section of the sheet member produce an audio signal providing information feedback of the amount of particles moving with the fluid.
CROSS REFERENCE TO RELATED APPLICATION
This Application is a continuation of U.S. application Ser. No. 487,676, filed July 11, 1974, now abandoned. Application Ser. No. 487,676 is a continuation of U.S. application Ser. No. 252,323, filed May 10, 1972, now abandoned. Application Ser. No. 252,323 is a continuation-in-part of U.S. application Ser. No. 37,157, filed May 14, 1970, now U.S. Pat. No. 3,674,316.
Disclosed is an elbow for use in pelletized plastic conveying systems. The elbow includes first and second legs disposed at an angle to each other with an impingement plate disposed therebetween. The impingement plate is positioned to deflect pellets traveling substantially parallel to the axis of the first leg to travel substantially parallel to the axis of the second leg. The elbow includes a funnel section positioned to receive particles deflected by the impingement plate and funnel them toward the second leg. The funnel section also reduces the velocity of the pellets in the vicinity of the impingement plate.
Vacuum cleaner for use in industry and household comprising a housing and an electric motor driving the blower generating the working vacuum, and optional maneuvering means for moving a suction nozzle over the material to be cleaned. There is provided in the area of the channel passed by the dust and dirt particles drawn in, an optical sensor comprising a light transmitter and a coacting light receiver so that the quantity of the dust and dirt particles drawn in at any time is detected. After comparison of the value so determined with a given threshold value, either a visual and/or an acoustic signal are obtained and/or a power variation of the electric motor driving the blower is effected.
The disclosure describes a vacuum cleaner having a dirt sensor circuit usable with an audio detector. The circuit provides amplification of the audio signal, a pulse stretcher, sensitivity selection of a non linear characteristic and visual signal means to indicate high or low levels of dirt concentration.
A vacuum cleaner for providing visual operational status indicators includes a vacuum cleaner having internal components that are indicative of the cleaner's performance. Sensors are coupled to at least one of the internal components to be monitored. A microprocessor receives input from the sensors, analyzes the input, and generates an output signal. Visual indicators are carried by the vacuum cleaner and receive the output signals to display the operational status of the vacuum.
A safety vacuum cleaner including a measuring system for residual dust monitoring, including a housing having an air passage with an inlet, an outlet, and a flow cross section. A turbine is disposed within the air passage and is rotatable to move an air stream through the air passage, the air stream containing dust particles. The turbine is electrically grounded such that electrical charges associated with the particles are removed upon contact of the particles with the turbine. A filter element is disposed within the air passage, and at least one electrode is disposed within the air passage downstream of the turbine, the electrode shaped as a grid covering the flow cross section of the air passage. The electrode conducts an electrical current responsive to contact with uncharged particles and emits a measurement signal indicative of the amount of the particles in the air stream.