Temp. control for passenger compartment of bus - regulates air flow by altering ventilation fan speed and fresh-air inlet flap

摘要

The temp. control has a sensor measuring the air flow in the air distribution channel. The channel's outlet holes are located in the passenger compartment. The sensor's output is connected to an air-flow regulator. The latter controls the speed of the fan in the channel and the drive that opens/closes the fresh-air inlet flap. The fan is on when the bus is stationary and its speed is gradually reduced as the bus's speed increases (increased flow of fresh air) until it is stopped altogether. The flap is then progressively closed as the speed increases further. The air flow is thereby kept constant irrespective of speed. A thermostat in the bus is coupled to the regulator so that the air flow can be increased when the temp. in the bus rises.