US 6,283,849 B1 · Vehicle filtration control system

Abstract

A vehicle air filtration system having a fine and coarse filters. The system is responsive to temperature to maximize filter life and filtration efficiency. During normal operation, air from within the cab is recirculated through a fine filter as fresh air from outside the cab is drawn in through a coarse filter. If a vehicle door or window is opened, the system stops recirculating air through the fine filter, begins exhausting air, and only draws in air through the coarse filter. After a period of time, the system again begins recirculating air through the fine filter and ceases drawing in air through the coarse filter and exhausting air. After a second period of time it returns to normal operation. If the door or window is open only briefly, the system stops recirculating air though the fine filter and begins recirculating air through the coarse filter along with the fresh air (and begins exhausting air). After a period of time, the system again begins recirculating air through the fine filter and ceases drawing in air through the coarse filter and exhausting air. After a second period of time it returns to normal operation.

Claims22

Dependent claims

A device for filtering particulate from air in a vehicle cab having at least one portal, comprising:

a first filter for filtering particulate from the air;
a first passageway for directing air through the first filter having an outlet changeable between a closed position ceasing air flow through the first filter and an open position allowing air flow through the first filter;
a sensor for sensing when the portal is open and outputting a signal;
and
a controller for receiving the signal from the sensor and changing the position of the first passageway for a selected period to reduce clogging of the first filter.

2 more elements

A device for filtering particulate from air in a vehicle cab having at least one portal, comprising:

a fine filter and a coarse filter for filtering particulate from the air, the fine filter being capable of filtering smaller particulate than the coarse filter;
a recirculating air passageway having an inlet originating in the cab and an outlet that is changeable between a fine filter position connecting the outlet to the fine filter and a coarse filter position connecting the outlet to the coarse filter, for recirculating air within the cab through the filters;
a sensor for sensing when the portal is open and outputting a signal;
and
a controller for receiving the signal from the sensor and changing the position of the recirculating passageway for a selected period to reduce clogging of the filters.

2 more elements

Dependencies are inferred from the claim text.

Vehicle filtration control system

Life of this patent

Vehicle filtration control system

Life of this patent

Abstract

Claims22