Filtering means and floor-sweeping machine provided with such means
AssigneeNilfisk-Advance, Inc.
InventorsJohn Black, Primo Granata
Life of this patent
Estimating the term…
Abstract
A filtering device filters out impurities contained in an air stream, and includes an inner filter plate, an outer frame that houses said filter plate thereinside, a structure for retaining said filter plate and conveying the shaking motion, a support socle applied on to said structure, a rotary electric motor, whose rotor is provided with one or more unbalanced masses, and which is fixedly mounted on said socle. The electric motor is operated in an intermittent manner, preferably with a direct-current, substantially square-wave supply voltage according to an ON-OFF cycling pattern, so as to generate a very broad spectrum of shaking frequencies that proves more effective in enabling impurities to be removed from the filter plate.
Claims9
A filter device for filtering out impurities contained in a stream of gas flowing through the filter device, the filter device comprising:
- an inner filter plate;
- an outer frame that houses said filter plate therewithin;
- a structure for retaining and supporting said filter plate, and for conveying shaking motion thereto, said structure being arranged on a face of said filter plate;
- a device for shaking and vibrating said structure, the device including
- a support base disposed on said structure,
- a rotary electric motor including a rotor provided with one or more unbalanced masses, the electric motor being fixedly mounted on said support base;
- and
- a control device for controlling a power supply of said electric motor in an ON-OFF cycling pattern,
- wherein said control device controls the power supply to said electric motor to be a direct-current supply voltage switched in an ON-OFF mode supplied in the form of a substantially square-wave voltage in a sequence comprising a pre-determined number of ON-OFF cycles.
A floor cleaning and sweeping machine for filtering a flow of air being taken in by suction, the machine comprising a filter device for filtering out impurities contained in a stream of gas flowing through the filter device, the filter device comprising:
- an inner filter plate;
- an outer frame that houses said filter plate therewithin;
- a structure for retaining and supporting said filter plate, and for conveying shaking motion thereto, said structure being arranged on a face of said filter plate;
- a device for shaking and vibrating said structure, the device including
- a support base disposed on said structure,
- a rotary electric motor including a rotor provided with one or more unbalanced masses, the electric motor being fixedly mounted on said support base;
- and
- a control device for controlling a power supply of said electric motor in an ON-OFF cycling pattern,
- wherein said control device controls the power supply to said electric motor to be a direct-current supply voltage switched in an ON-OFF mode supplied in the form of a substantially square-wave voltage in a sequence comprising a pre-determined number of ON-OFF cycles.
Dependencies are inferred from the claim text.