US2311294A - Refrigeration apparatus for air conditioned passenger vehicles - Google Patents

Description

M. E. HANSON Filed NOV. 15, 1941 um \QEFEQSQE T I AN mm mm. \m

kOWmQQQZDU Feb. 16, 1943.

REFRIGERATION APPARATUS FOR AIR CONDITIONED PASSENGER VEHICLES by W J% Patented Feb. 16, 1943 DB'dl U uum REFRIGERATION APPARATUS FOR AIR CON- DITIONED PASSENGER VEHICLES Milton E. Hanson, Haddonficld, N. J., assignor to B. F. Sturtevant Company, Boston, Mass.

Application November 13, 1941, Serial No. 418,910

2 Claims.

This invention relates to refrigeration apparatus for air conditioning, and relates more particularly to refrigeration apparatus for air conditioned passenger vehicles, which apparatus is driven by internal combustion engines.

Due to the loads of the axle driven refrigeration equipment of air conditioned, railway passenger cars on the locomotive, it is desirable to energize the refrigeration equipment by auxiliary internal combustion engines utilizing fuels such, for example, as propane. This invention provides refrigeration apparatus so energized and provides controls for the efflcient operation of the equipment.

A feature of the invention resides in continu-. ously operating the internal combustion engine at idling speed during periods of reduced load when refrigeration is not required and disconnecting the compressor therefrom as by a centrifugal clutch.

Other features of the invention reside in starting and stopping the engine and operating it at different speeds, under thermostat control to take care of all operating conditions.

Objects of the invention are to improve the performance of and to reduce the maintenance cost of refrigeration apparatus driven by an internal combustion engine.

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

Fig. 1 is a diagrammatic view of a railway passenger car conditioning system embodying this invention, and

Fig. 2 is an internal view of one form of a centrifugal clutch which may be used for driving the compressor of Fig. 1 by the engine thereof.

The blower 5 of Fig. 1, draws outdoor air through the inlet 6, and recirculated air from the passenger space through the inlet I, passes it through the conditioner 8 and then through the usual overhead duct 4, into the passenger space.

The conditioner 8 includes a refrigerant evaporator for cooling the air, which evaporator comprises the inlet header tubes 9 connected to the expansion valve and distributor I3, and the inlet header tubes ll connected to the expansion valve l2. The evaporator also comprises the suction header tubes 13 connected by the suction line H, which includes the valve I5, and by the suction line I! to the suction side of the compressor ll. The evaporator also comprises the suction header tubes 13 connected by the suction line I! to the suction line I3.

The compressor I! supplies refrigerant through the supply line 23, the condenser 2|, the valve 22, the receiver 23, the drier 24, the valve 25, the supercooler 23, the pressurestat 21 and supply line 23 to the expansion valve distributors l0 and I2.

All of the evaporator tubes are enclosed by the usual spaced, vertical, sheet fins 59. By having alternate suction header tubes connected to the different suction lines It and I3 and by closing the valve I! in the line H, one-half of the evaporator may be rendered inactive, yet the active tubes will extend across the air stream and through the use of the common interconnectin fins 23 will act to cool and dehumidify the air in the areas of the inactive tubes thus preventing the reevaporation of moisture into the air stream, previously condensed when the inactive tubes were active.

The compressor I1 is driven through the centrifugal clutch 23 by the internal combustion engine 30. The fan 3| on the engine shaft 32 moves air through the condenser 21 to cool same.

The centrifugal clutch 29 includes the inner clutch member 33 connected to the engine shaft, the outer clutch members 34 which are pivoted at 35 and connected to the governor type balls 36. At engine speeds below 600 R. P. M., the balls 35 assume the position illustrated by Fig. 2 with the outer clutch members 34 out of contact with the inner clutch member 33. At speeds above 600 R. P. M., the balls 36 move outwardly through centrifugal force and move the outer clutch members 34 in tight contact with the inner clutch member 33. The outer clutch members are connected at the pivots 35 to the shell of the clutch 29 and through same to the shaft 31 of the compressor so that the compressor is connected to the engine at engine speeds above 600 R. P. M. and is disconnected from the engine at lower engine speeds.

The three thermostats 33, 33 and 40 are mounted above the inlet 1 in the path of the recirculated air from the passenger space. The thermostat 33 is an electric thermostat and closes its contacts at say 72 F. to close an electric circuit including the relay 4|, the ignition equipment 43, and the starter motor 42, for starting the engine 33. The starter equipment may be of the well known Startex type in general use on the higher prices automobiles for maintaining the engine in operation so long as the thermostat 33 has its contacts closed.

The thermostat 33 is of the modulating bellows type and is connected by the tube 44 to the bellows actuating element 45 which adjusts the throttle valve of the carburetor 46 for varying the speed of the engine 30. At say 76 F., the engine speed may be maintained at about 1200 R. P. M. At say 82 F., the engine speed may be maintained at about 1600 R. P. M. which may be full speed. The volume of refrigerant delivered by the compressor varies with engine speed so that increased refrigeration is provided when required.

The thermostat 40 which is electric, closes its contacts at below say 76 F., causing energization of the solenoid 41 causing the valve IE to close and one section of the evaporator to become inactive thus decreasing the evaporator surface for reduced loads.

The pressurestat 2! acts when the head pressure in the line 28 rises above 180 pounds, to close the electric circuit of the motor 48 causing it to operate the fan 49 for moving air through the super-cooler 26, and to operate the pump 50 causing it to draw water from the tank 5| and to supply it through the pipe 52 to the spray nozzle 53 which sprays water upon the tubes of the super-cooler for the evaporative cooling thereof.

While one embodiment of the invention has been described for the purpose of illustration, it should be understood that the invention is not limited to the exact apparatus and arrangement of apparatus illustrated, as modifications thereof may be suggested by those skilled in the art without departure from the essence of the invention.

What is claimed is:

l. Refrigeration apparatus for air cooling comprising means including an evaporator forming an air cooler, means including a compressor for supplying refrigeration to said evaporator, an internal combustion engine for driving said compressor, mea means responsive to tempegatum c'served for star g said engine when the space temperature is above a predetermined point, for reducing the effective surface of said evaporator and for reducing the speed of said engine when the space temperature has fallen below another predetermined point, amt-13m 'r'emicing the speed of said engine toggling speed when the space tem'- perature has a en to a predetermined point belowsaid Ia'st" mentioned predetermined point, and a CEI1I1IE81 clutch between said compressor and engine or sconnecting sa compressor from said engine at idling speed.

2. Refrigm apparatus for air cooling comprising means including an evaporator forming an air cooler, means including a compressor for supplying refrigeration to said evaporator, an internal combustion engine for driving said compressor, means including means responsive to temperature changes in the space served for reducing the effective surface of said evaporator and for reducing the speed of said engine when the space temperature has fallen to a predetermined point, and for reducing the speed of said engine to idling speed when the space temperature has fallen to a predetermined point below said last mentioned predetermined point, and a centrifugal clutch between said compressor and engine for disconnecting said compressor from said engine at idling speed.

MILTON E. HANSON.

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