Time-extended cooling system for line-powered apparatus

Abstract

Certain electrical systems, such as projectors, contain components, which get very hot and require active cooling systems. During normal operation, a switch operates a cooling fan from a primary power supply. Upon detecting a failure in the primary power supply, the switch connects the cooling fan to a secondary power supply.

1 . A time-extended cooling apparatus, comprising: 
 means for cooling;    a primary power supply connected to the means for cooling;    a secondary power supply connected to the means for cooling;    means for operating the means for cooling from the primary power supply;    means for sensing a failure in the primary power supply; and    means for switching the means for cooling to the secondary power supply in response to sensing the failure in the primary power supply.    
   
   
       2 . The apparatus of  claim 1  wherein the means for cooling is a fan.  
   
   
       3 . The apparatus of  claim 1  wherein the means for cooling is a liquid cooling system.  
   
   
       4 . The apparatus of  claim 1  wherein the means for cooling is a Peltier device.  
   
   
       5 . The apparatus of  claim 1  wherein the means for cooling is a refrigeration system.  
   
   
       6 . The apparatus of  claim 1  further comprising: 
 a projector lamp generating heat.    
   
   
       7 . The apparatus of  claim 1  wherein the secondary power supply is a rechargeable battery.  
   
   
       8 . The apparatus of  claim 1  wherein the secondary power supply, means for operating, means for sensing, and means for switching are embedded in the means for cooling.  
   
   
       9 . The apparatus of  claim 1  wherein the secondary power supply is a spring.  
   
   
       10 . The apparatus of  claim 1  wherein the secondary power supply is a capacitor.  
   
   
       11 . The apparatus of  claim 1  wherein the means for operating maximizes a time the means for cooling operates.  
   
   
       12 . The apparatus of  claim 1  further comprising: 
 means for sensing a temperature of a component cooled by the means for cooling.    
   
   
       13 . The apparatus of  claim 1  further comprising: 
 a heat sensitive device;    means for sensing a temperature of the heat sensitive device; and    means for operating the means for cooling from the secondary power supply until the heat sensitive device reaches a predetermine reduced temperature.    
   
   
       14 . The apparatus of  claim 13  wherein the heat sensitive device is a projector lamp.  
   
   
       15 . A time-extended cooling apparatus, comprising: 
 means for cooling mounted in close proximity to a lamp in a projector;    a primary power supply connected to the means for cooling;    a secondary power supply connected to the means for cooling;    means for operating the means for cooling from the primary power supply;    means for sensing a failure in the primary power supply;    means for sensing a temperature of the lamp; and    means for switching the means for cooling to the secondary power supply in response to sensing the failure in the primary power supply until the lamp reaches a predetermined reduced temperature.    
   
   
       16 . A method for time-extended cooling, comprising: 
 operating a cooling system from a primary power supply;    sensing a failure in the primary power supply; and    operating the cooling system from a secondary power supply in response to sensing the failure in the primary power supply.    
   
   
       17 . The method of  claim 15  further comprising: 
 sensing a temperature of a heat sensitive device; and    operating the cooling system from a secondary power supply until the heat sensitive device reaches a predetermined reduced temperature.