Air compressor with self contained cooling system

Abstract

Provided is a self-contained, closed-loop cooling system for an air compressor, and a method of controlling a temperature of the compressor. The air compressor provides compressed air to an associated system. The air compressor includes a passage for a flow of coolant therethrough. A pump pumps an input flow of coolant into the air compressor, and a heat exchanger cools an output flow of coolant from the air compressor. Fluid delivery lines connect the air compressor, the pump, and the heat exchanger in a closed loop configuration, such that the coolant is not subject to contact with atmospheric air or other systems. The cooling system is associated solely with the air compressor for cooling its parts.

What is claimed is: 
     
         1 . A closed-loop cooling system comprising:
 an air compressor including at least one passage for a flow of coolant therethrough to cool its parts;   at least one temperature sensor located in the air compressor for measuring a temperature of the coolant;   a pump for pumping an input flow of coolant into the at least one passage of the air compressor; and   a heat exchanger for cooling an output flow of coolant from the at least one passage of the air compressor,   wherein a rate of flow of the coolant is based on the temperature of the coolant measured by the at least one temperature sensor.   
     
     
         2 . The system according to  claim 1 , further comprising a fan for moving air across the heat exchanger to cool the output flow of coolant wherein a speed of the fan is based on the temperature of the coolant measured by the at least one temperature sensor. 
     
     
         3 . The system according to  claim 1 , wherein the flow of coolant is distributed via the plurality of fluid delivery lines connecting the pump, heat exchanger, and air compressor. 
     
     
         4 . The system according to  claim 3 , wherein the plurality of fluid delivery lines comprises:
 an input line connected between the pump and the air compressor for delivery of the input flow of coolant from the pump into the at least one passage of the air compressor;   an output line connected between the air compressor and the heat exchanger for delivery of the output flow of coolant from the at least one passage of the air compressor to the heat exchanger; and   an intermediate line connected between the heat exchanger and the pump for delivery of the cooled output flow of coolant from the heat exchanger to the pump.   
     
     
         5 . The system according to  claim 1 , wherein the associated system is an air brake system. 
     
     
         6 . The system according to  claim 4 , further comprising a control valve situated along the input line configured for movement between open and closed positions to allow or limit the input flow of coolant into the at least one passage of the air compressor. 
     
     
         7 . The system according to  claim 1 , further comprising a controller configured to adjust the rate of flow of the coolant based on the temperature of the coolant. 
     
     
         8 . The system according to  claim 1 , wherein the coolant is polypropylene glycol. 
     
     
         9 . A self-contained closed-loop cooling system for a vehicle comprising:
 an air compressor operable to produce compressed air, the air compressor including at least one passage for flow of coolant therethrough;   a pump for pumping an input flow of coolant into the at least one passage of the air compressor;   a heat exchanger for cooling an output flow of coolant from the at least one passage of the air compressor; and   wherein the self-contained closed-loop cooling system is independent of an engine cooling system of the vehicle.   
     
     
         10 . The system according to  claim 9 , further comprising a fan for moving air across the heat exchanger to cool the output flow of coolant. 
     
     
         11 . The system according to  claim 9 , wherein the flow of coolant is distributed via the plurality of fluid delivery lines connecting the pump, heat exchanger, and air compressor. 
     
     
         12 . The system according to  claim 11 , wherein the plurality of fluid delivery lines comprises:
 an input line connected between the pump and the air compressor for delivery of the input flow of coolant from the pump into the at least one passage of the air compressor;   an output line connected between the air compressor and the heat exchanger for delivery of the output flow of coolant from the at least one passage of the air compressor to the heat exchanger; and   an intermediate line connected between the heat exchanger and the pump for delivery of the cooled output flow of coolant from the heat exchanger to the pump.   
     
     
         13 . The system according to  claim 9 , further comprising a controller configured to at least adjust a rate of flow of the coolant based on the temperature of the coolant. 
     
     
         14 . The system according to  claim 10 , wherein a speed of the fan is based on a temperature of the coolant measured by at least one temperature sensor. 
     
     
         15 . The system according to  claim 9 , further comprising at least one temperature sensor located in the at least one passage of the air compressor for measuring a temperature of the coolant, wherein a rate of flow of the coolant is based on the temperature of the coolant measured by the at least one temperature sensor. 
     
     
         16 . The system according to  claim 9 , wherein the coolant is polypropylene glycol. 
     
     
         17 . A locomotive comprising:
 an engine;   an engine cooling system; and   a self-contained air compressor system comprising:
 an air compressor operable to produce compressed air, the air compressor including at least one passage for flow of coolant therethrough; 
 a pump for pumping an input flow of coolant into the at least one passage of the air compressor; 
 a heat exchanger for cooling an output flow of coolant from the at least one passage of the air compressor; and 
 a plurality of fluid delivery lines connecting the air compressor, the pump, and the heat exchanger in a closed loop configuration for the flow of coolant therethrough; 
   wherein the self-contained air compressor system is separate and not coupled to the engine cooling system.   
     
     
         18 . The locomotive according to  claim 17 , further comprising a controller configured to at least adjust a rate of flow of the flow of coolant based on the temperature of the coolant. 
     
     
         19 . The locomotive according to  claim 17 , further comprising a fan for moving air across the heat exchanger to cool the output flow of coolant. 
     
     
         20 . The locomotive according to  claim 19 , further comprising at least one temperature sensor located in the at least one passage of the air compressor for measuring a temperature of the coolant, wherein a rate of flow of the coolant and a speed of the fan are based on the temperature of the coolant measured by the at least one temperature sensor. 
     
     
         21 . A method of controlling a temperature of an air compressor of a locomotive configured to receive and compress air from an air source, the air compressor comprising a passage for flow of coolant therethrough, the passage in closed communication with a pump and a heat exchanger; the method comprising:
 pumping coolant to the air compressor using the pump to deliver coolant to the air compressor;   passing the flow of coolant through the passage of the air compressor;   outputting coolant from the passage of the air compressor to the heat exchanger;   removing heat from the coolant with the heat exchanger; and   delivering the coolant from the heat exchanger to the pump for pumping,   wherein a temperature of the coolant in the passage is determined using at least one temperature sensor located in the air compressor and wherein a rate of flow of the coolant is based on the temperature of the coolant.   
     
     
         22 . The method of  claim 21 , wherein the at least one temperature sensor comprises a first temperature sensor located at an inlet of the passage for generating a first temperature reading and a second temperature sensor located at an output of the passage for generating a second temperature reading. 
     
     
         23 . The method of  claim 22 , wherein the temperature of the coolant is determined by computing the average of the first temperature reading generated by the first temperature sensor and the second temperature reading generated by the second temperature sensor.