Electro-hydraulic brush down force control
US5943724A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 13, 1998 |
| Grant date | Aug 31, 1999 |
| Priority date | — |
| Expiry date | Jan 13, 2018 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE01H1/05
- WIPO fieldFurniture, games
- WIPO sectorOther fields
Abstract
A floor cleaning machine of the type having a fluid driven scrub brush utilizes fluid pressure for applying down force on the scrub brush to a floor surface being cleaned. The fluid pressure applied is controlled by a fluid pressure regulator which has a movable valve element and an electrical coil for controlling the position of the movable valve element. There is a feedback circuit for controlling current through the coil which includes a source of power and a pulse width modulation switching device. The switching device in turn is controlled by a comparison between the current sensed in the coil circuit and an operator set value for the desired current to provide a desired down force on the cleaning brush.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.