Patent ID: 6592302
Filing Date: 2003-07-15
Classification: B65G

Abstract:
A blower unit adapted for use in a pneumatic transmission system comprising:a housing having first and second inlet/outlet openings through which air can flow, a first blower, disposed within said housing, for moving a volume of air from said first inlet/outlet opening to said second inlet/outlet opening; a first bypass path, disposed within said housing, through which air can flow from said second inlet/outlet opening to said first inlet/outlet opening without flowing through said first blower; and a first valve element, disposed in said first bypass path, for substantially blocking a flow of air through said first bypass path when said first blower is active; a second blower, disposed within said housing, for moving a volume of air from said second inlet/outlet opening to said first inlet/outlet opening; a second bypass path, disposed within said housing, through which air can flow from said first inlet/outlet opening to said second inlet/outlet opening without flowing through said second blower; and a second valve element, disposed in said second bypass path, for substantially blocking a flow of air through said second bypass path when said second blower is active; wherein said first and second blowers are mounted in said housing such that said second blower is downstream of said first blower when air is flowing from said first inlet/outlet opening to said second inlet/outlet opening and said first blower is downstream of said second blower when air is flowing from said second inlet/outlet opening to said first inlet/outlet opening.