Patent ID: 6928830
Filing Date: 2005-08-16
Classification: B60H

Abstract:
1. A refrigeration unit for conditioning and circulating air in a trailer, said refrigeration unit including an evaporator fan located downstream of an evaporator and a microprocessor for controlling and recording conditions in said trailer, said refrigeration unit further including: said fan producing a suction pressure upstream thereof and a discharge pressure downstream thereof; two flow paths between said interior of said trailer and ambient atmosphere surrounding said trailer; manually operated means for simultaneously controlling discrete positions between and including closed and fully open positions of said two flow paths between said interior of said trailer and said ambient atmosphere surrounding said trailer; a first one of said two flow paths is for supplying atmospheric air to air returning from circulating, in said trailer and extends from a point which is just upstream of said fan and which is at suction pressure and said ambient atmosphere whereby atmospheric air is supplied to circulating air; a second one of said two flow paths is for discharging circulating air from said trailer to said ambient atmosphere and extends to said ambient atmosphere from a point which is just downstream of said fan and which is at discharge pressure; said manually operated means including valve means which seat on and are axially reciprocatable with respect to respective portions of said two flow paths and manually positionable means secured to said valve means so as to be axially reciprocatable therewith and, additionally, rotatable with respect thereto for setting the position of said manually operated means.