Citations:butterfly door

A door which pivots on a central axis

 * 2004, Don Knowles, Jack Erjavec, Basic Automotive Service and Maintenance, ISBN 1401852084.
 * As the engine warms up, the temperatuere switch in the air cleaner should gradually shut off the vacuum to the butterfly door actuator and the butterfly door slowly moves to open the cold air passage into the air cleaner.


 * 1991, American Aviation Historical Society Journal, Volumes 36-37, p. 172
 * Simultaneous with the butterfly door closing, another electrical actuator in the fuel line of each J85 would also close a fuel valve, thus shutting the engine down.


 * 2002, Masahiro Ito, "Door for changing over air passage" US patent US6412755 B2
 * According to another aspect of the present invention, there is provided a door for changing over the air passage, comprising a butterfly door (D1) having a rotary shaft (13) arranged at the central portion of a door plate (10)...


 * 2000, 	Masahiro Ito, Kousei Banno, "Air passage switching system for air conditioner", US patent US6047951 A
 * An air passage switching system includes a case forming an air passage, and a butterfly door for opening and closing the air passage. The door includes a door body, a rotation shaft for rotating the door body, and a seal member attached to the door body.


 * 2001, Stefan Schwarz, "Motor vehicle heating or air conditioning unit", US patent US6278083 B1
 * The first butterfly door has a central pivot 52 and two opposed shutter portions 53 dimensioned such that when the butterfly door 51 is in a first orientation the shutter portions abut respectively the first extremity 31 and the first wall portion 11.


 * 1989, B. Romine Jr., B. Meyer, R. Re, "A static investigation of several STOVL exhaust system concepts", 25th Joint Propulsion Conference, AIAA/ASME/SAE/ASEE.
 * The butterfly door concept, Figure 3. featured a pair of butterfly type inner doors to seal off the ventral nozzle in cruise flight and modulate flow in conjunction with the rear nozzle and forward post lift system during transition.