05276933 is referenced by 17 patents and cites 7 patents.

A surface maintenance machine includes a cylindrical brush mounted in the machine for rotation about a generally horizontal axis extending transverse to the direction of machine movement. A recirculation flap is attached to the machine and extends generally coextensively with the brush and parallel thereto. The recirculation flap is normally yieldingly urged toward the brush, with contact between the flap and a floor obstacle causing the flap to move, against the force of its mounting springs, away from the brush.

Title
Damage resistant recirculation flap
Application Number
7/909222
Publication Number
5276933
Application Date
July 2, 1992
Publication Date
January 11, 1994
Inventor
Michael S Wilmo
Crystal
MN, US
Robert D Hennessey
Golden Valley
MN, US
Agent
Kinzer Plyer Dorn McEachran & Jambor
Assignee
Tennant Company
MN, US
IPC
E01H 1/04
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