US2286252A - Air conditioning system utilizing refrigeration - Google Patents

Description

Jlme 1942- c. o. BERGSTROM 2,286,252

AIR CONDITIONING SYSTEM UTILIZING REFRIGERATION v 2- Sheets-Sheet 1 Original Filed July 13, 1939 1 m IHIIJ l 1 INVENTOR.

C424. 0. Bzzssrepm I @ami J M ATTORNEY.-

June 16, 1942. c; o. BERGSTROM 2,286,252

AIR CONDITIONING SYSTEM UTILIZING REFRIGERATION Original Filed July 13, 1959 2 Sheets$heet 2 EvAPoRA TOR ELECTRIC SOURCE INVENTOR. CARL 0. Bazaar-20M ATTORNEY.

, Patented June 16, 1942 AIR CONDITIONING SYSTEM UTILIZING REFRIGERATION Carl O. iBergstrom, Boston, Mass, assignor to B. F. Sturtevant Company, Boston, Mass.

Original application July 13, 1939, Serial No.

284,262, now Patent No. 2,258,565, dated Octoher 7, 1941. Divided and this application May 8, 1940, Serial No. 333,918

3 Claims. (Cl. 98-10) This invention relates to air conditioning systems for passenger vehicles, utilizing refrigeration and has as its object to save in refrigeration when outdoor conditions are right for effective cooling to be accomplished through supplying an increased volume of outdoor air.

This application is a division of my copending application, Serial No. 284,262 filed July 13, 1939, now Patent No. 2,258,565, October 7, 1941.

On. some railroad lines, it is possible to affect suflicient cooling, in summer, by forcing large volumes of outdoor air through the cars. There are brief periods, however, on such lines when a relatively small amount of refrigeration for cooling is desired. This invention provides efficient apparatus at low cost for combining refrigerative cooling with pressure ventilation under effective thermostatic control.

The invention will now be described with reference to the drawings, of which:

Fig. l is a plan view looking downwardly upon a railway passenger car embodying this invention, with a portion of the roof removed, and a portion in section;

Fig. 2 is an elevation view with a portion of the side removed, and a portion in section of the passenger car of Fig. 1;

Fig. 3 is a sectional view along the lines 33 of Fig. 2, and

Fig. 4 is a diagrammatic view of the automatic controls employed.

The car 5 has the longitudinal duct 6 mounted in the roof zone above the ceiling. The lower wall of this duct may form the ceiling of the car. The lower wall of the duct is perforated to receive the centrifugal fans I which extend into the passenger space and which are fitted with horizontal deflectors I5 for discharging air in horizontal streams into the passenger space. The fans preferably employed are those of my Patent No. 2,142,834 which issued Jan. 3, 1939.

The two air cooling evaporators 8 are mounted in the duct 6 adjacent the longitudinal center inlets II could of course, be arranged in the ends or sides of the duct.

thereof, one on each side of the recirculated air inlet 9, which is in the lower wall of the duct at the longitudinal center thereof. The dampers I0 are adjustable as will be explained later, to control the volume of recirculated air.

The duct 6 contains in its upper wall, the fresh air inlets II with dampers I2. The ventilators I3 which contain the air filters I4 are in the sides of the car and supply outdoor air which passes along the side of and top of the duct and enters the inlets I I under the suction of the fans I. The

Referring now to Fig. 4; the thermostat I6 which may be mounted in the outdoor air stream or in the passenger space, controls the conversion from pressure to refrigerative cooling and vice versa. By way of example, when the temperature of the outdoor air is below say F., the contacts of the thermostat I6 are open and the relays I1 and I8 and the compressor motor are deenergized through being disconnected from the electric source 20. The contacts of the relay II are closed and complete the electric circuit including the electric source 20, the wires 2 I, 22, 23, 24, 25 and 26 and the dampermotors 21, causing the. motors 21 to adjust the fresh outdoor air dampers I2 to full open position. At this time,

the contacts of the relay I8 are open causing the electric circuit including the electric source 20, the wires 23, 22, 3|, the recirculated air damper motor 30, the wires 29, the contacts of the relay I2, and the wires 28, 25 and 24 to be deenergized. This causes the motor 30 to adjust the recirculated air dampers to fully closed position. At the same time, the compressor motor I9'is deenergized due to the contacts of the thermostat I6 which are in series with it and the electric source 20, being separated.

Thus when the temperature of the outdoor air is below 80 F., the compressor 32 which in cooperation with the condenser 33 and the expansion valve 34, supplies the evaporators 8 with refrigerant, is shut down, and the fans I draw in, for example 4200 cubic feet per minute of outdoor air through the inlets II and I3, and supplyit into the passenger space.

, When the temperature of the air rises above- 80 F., the, thermostat I6 closes its contacts; the

solenoids of the relays I! and I8 are energized with the result that the damper motors adjust the outdoor air dampers to closed or substantially closed positions; the damper motor 30 adjusts the recirculated air dampers III to wide open position, and the compressor motor I9 is energized to drive the compressor 32.

The fans I now operate against a, higher pressure which reduces the air volume to about 2,000 cubic feet of air :per minute. There will be a leakage through the fresh air dampers I2 providing about 25% of outdoor air. The recirculated air through the inlet 0 passes through the evaporators 8, is mixed inthe duct i with they outdoor air and then discharged into the passenger space.

This design provides a relatively inexpensive 1. An air cooling system for a passenger vehicle comprising a longitudinal duct overhead the passenger space, means for admitting outdoor air at a plurality of points into said duct, means ior admitting air from the passenger space into said duct adjacent the longitudinal center thereof, said duct having a plurality oi longitudinally spaced apertures in its lower wall, and a plurality of fans communicating with said duct through said apertures and with the passenger space for drawing outdoor air through said first mentioned means and recirculated air through said second mentioned means and for discharging it, into the passenger space.

2. An air cooling system for a passenger vehiclecomprising a longitudinal duct overhead the passenger space, means for admitting outdoor air at a plurality of points into said duct, means for admitting air from the passenger space into said ductadjacent the longitudinal center thereof, air cooling means in said duct adjacent the longitudinal center thereof in the path of the recirculated air admitted through said last mentioned means, said duct having a plurality of longitudinally spaced apertures in its lower wall, and a plurality of fans communicating with said duct through said apertures and with the passenger space Iordrawing outdoor air through said first mentioned means and recirculated air through said second mentioned means and for discharging it into the passengerspace.

3. An air cooling system for a passenger vehicle comprising a longitudinal duct overhead the passenger space, means for admitting outdoor air at a plurality 01' points into said duct. means for admitting air from the passenger space into said duct adjacent the longitudinal center thereof, air coolingmeans in said'duct on opposite sides of said last mentioned means in the path 01 the recirculated air admitted therethrough,

said duct having a plurality of longitudinally spaced apertures in its lower wall, and a plurality of fans communicating with said duct through said apertures and with the passenger space for drawing outdoor air through said first mentioned means and recirculated air through said second i mentioned means and tor discharging it into the passenger space.

CARL O. BERGSTROM.

Images