Air conditioning system for a railway car having two single-storey end compartments and a two-storey central compartment

The heating and ventilating system for a railway car having two single-storey end compartments (A, B) and a two-storey (C1, C2) central compartment (C), comprises heating/ventilating units (1A, 1B) in the top parts of each end compartment, each supplying a transverse distribution duct (3A, 3B) connected to two longitudinal ducts (4A, 5A; 4B, 5B) blowing into the end compartment and to two other longitudinal ducts (10A, 11A; 10B, 11B) blowing into one storey of the central compartment. The four longitudinal ducts (10A, 11A; 10B, 11B) blowing into the central compartment are located in two casings (20) forming part of the floor structure of said second storey, both ducts from one of the air units being provided with auxiliary, vertical ducts (12).

This invention concerns an air conditioning system for a railway car having 
two single-level end compartments and one two-level central compartment, 
the system comprising, in the top part of each end compartment, a heating 
and ventilating plant, hereinafter termed "air unit", feeding a transverse 
distribution duct connected to two longitudinal ducts blowing into the end 
compartment and also connected to two other longitudinal ducts blowing 
into one of the levels of the two-level central compartment, said central 
compartment thus comprising four longitudinal ducts. 
In the prior art air conditioning systems of this type, the central 
compartment comprises two ducts at floor level in the first level and two 
ducts at floor level in the second level. 
At the floor level of this second level, the two ducts are add-on elements 
not forming part of the floor structure. The second storey floor therefore 
extends from one side to the other of the car and thus presents a 
considerable cantilever, which is a source of unwanted vibrations. 
This invention is directed to reducing the cantilevering of the second 
storey floor and thus bringing about a greater rigidity. This goal is 
attained by providing a casing to each side of the second storey floor, 
which limits the width of said floor. Moreover, in order to simplify the 
construction of such a duct system, the two ducts of the prior art, 
located at the floor level of the first storey, are according to the 
invention installed instead at the level of the second storey floor and 
each integrated into a casing. 
The inventive duct system has four longitudinal ducts blowing into the 
central compartment, but these ducts are arranged in two casings being 
part of the structure of the second storey floor, the two ducts of one air 
unit having vertical auxiliary ducts appended thereto. 
In a first embodiment of the invention, each vertical auxiliary duct is 
provided at one end with a diffuser operable to direct air at the level of 
the feet of passengers in the first level, the two longitudinal ducts of 
the other air unit being provided along their lengths with evenly spaced 
diffusers to blow air out at the level of the feet of the passengers in 
the second level. 
According to a second embodiment, each vertical appended duct is provided 
at one end thereof with a diffuser operable to direct air at head level of 
the passengers in the second level, the two longitudinal ducts of the 
other air unit being provided along their lengths with evenly spaced 
diffusers to blow air at head level of the passengers in the first level, 
this second mode being mainly reserved for cool air blowing.

FIGS. 1 and 2 are schematic drawings of a railway car having two end 
compartments A, B and a central compartment C, the latter having two 
levels C1, C2 which are more readily distinguishable in FIGS. 3 and 4. 
In the air conditioning system illustrated in FIG. 1, each car end 
compartment A, B comprises a heating and ventilation unit 1A, 1B which 
draws air from the outside of the car through a grill 2--only one grill 2A 
being depicted in the drawing--and blows into a transverse duct 3A, 3B 
connected to two longitudinal ducts 4A, 5A; 4B, 5B supplying air to the 
end compartment A, B respectively, and to two other longitudinal ducts 6A, 
7A; 6B, 7B supplying the central compartment C. The two longitudinal ducts 
6A, 7A of air unit 1A are located one to each side of the second level of 
the central compartment, at floor level. The two longitudinal ducts 6B, 7B 
of unit 1B are located one to each side of the first level of the central 
compartment, at floor level. 
The four ducts 6A, 7A, 6B, 7B of the central compartment supply air to the 
two car levels via diffusers 8 distributed along their entire lengths. 
FIG. 2 shows an air conditioning system comprising, in each end 
compartment, like elements to those of FIG. 1, namely a heating and 
ventilation unit 1A, 1B drawing air from the outside via a grill 2 only 
one grill 2A being depicted in the drawing--and blowing into a transverse 
duct 3A, 3B connected to two longitudinal ducts 4A, 5A; 4B, 5B supplying 
the end compartment A, B respectively, and into two other longitudinal 
ducts 10A, 11A; 10B, 11B supplying the central compartment. The two 
longitudinal ducts 10A, 11A of end compartment A, as 6A and 7A in FIG. 1, 
are located at floor level of the second storey, but, in accordance with 
the invention the longitudinal ducts 10B, 11B of end compartment B are 
also located at the level of the second storey floor. 
The two ducts 10A, 11A have diffusers 13 distributed along their entire 
lengths and the two ducts 10B, 11B are provided, in accordance with the 
first embodiment of the invention, with appended vertical ducts 12 evenly 
spaced along their lengths. The end of each vertical duct 12 is equipped 
with a diffuser 14. Diffusers 13 and 14 are readily apparent in FIGS. 3 
and 4. 
Duct 10A of unit 1A supplies one side of the second storey of the central 
compartment, at floor level, and duct 11A of unit 1A supplies the other 
side of the second storey, at floor level. 
Duct 10B of unit 1B supplies, via its appended ducts 12, one side of the 
first storey of the central compartment, at floor level, and duct 11B of 
unit 1B supplies, via its appended ducts 12, the other side of the first 
storey, at floor level. 
FIG. 3 shows in half cross-section along III--II of FIG. 2 the central 
compartment and its two storeys C1, C2 each equipped with a floor, 22, 23 
respectively. The floor 22 is connected to a casing 20 contributing to the 
rigidity of said floor and, obviously, the other side of floor 22 not 
shown is connected to another casing 20. 
The casing 20 illustrated encloses the two ducts 10A, 10B separated by a 
partition 21 and the casing not shown encloses the two ducts 11A, 11B also 
separated by a partition. 
Duct 10A and duct 11A not shown are provided with diffusers 13 along their 
entire lengths, supplying air to the second storey C2 at its floor level 
22. Each vertical auxiliary duct 12 of ducts 10B and 11B not shown 
supplies air to the first storey C1 at the level of the floor 23 thereof 
via a diffuser 14. 
In the second embodiment illustrated in FIG. 4, the ducts 10A, 11A are the 
ones provided with auxiliary ducts 12, each said auxiliary duct having a 
diffuser 14 which supplies air to the second storey at ceiling level, the 
ducts 10B, 11B being provided with diffusers 13 which supply air to the 
first storey at ceiling level.