Duct distributor unit

DUCT DISTRIBUTOR UNIT

This assembly, shown in cross section below, is the main component of the system and it comprises a duct (1) and a heater distributor unit (2).

The duct (1) is formed of two parts, a lower one and an upper one; the right part of the latter is suitably shaped so that it mates perfectly with the upper right part of the dashboard surface (area under the windscreen of the partition between the engine and passenger compartments) with which it is in contact.

On the upper part of the right hand side of the duct there are two rectangular openings; the first is in an almost horizontal position and coincides with the one on the dashboard thus it communicates with the outside enviroment, while the other faces the passenger in an almost vertical position and allows the inlet of the air to the passenger compartment.

In the upper inner part of the duct there is a flap (3) which, duly directed by the special actuator, can take a position between the limits for closing of one of the above-mentioned openings.

Inside the duct on the lower part in correspondence with the above-mentioned openings, there is a fan (4) which, duly supplied at different voltages can turn at different speeds.

Between the duct (1) and the distributor (2) there is the evaporator (6).

The heater - distributor unit is mainly composed of a box housing the following:

• in the central position, a mixing port which duly directed by a knob through a bowden cable allows or prevents the entire flow of air taken in by the fan (4) or part of it to flow on the finned surface of the heater radiator (5);
• at the bottom centre, the heater radiator (5) the inlet and outlet fittings of which jut from the right side surface of the above-mentioned unit;
• above and at the front, four flaps which duly directed by a knob through a bowden cable, a toothed sector, a disk with grooves acting as distributor, shutter or fully close the section of the inside ducts which send air respectively to the feet, front vents and to the windscreen demisting vents.