Vacuum activated thermal covering

Abstract

A chemically activated thermal covering containing a thermogenic system and a carrier is provided. The thermogenic system contains at least one compartment which itself contains a first reagent. The first reagent is maintained at a first pressure. The system also contains an actuator for controllably isolating a second reagent from the first reagent. The second reagent is maintained at a second pressure which is higher than that of the first reagent. Channels connect the compartment to the actuator. The pressure differential between the first and second reagents draws the second reagent into the compartment thereby initiating a thermal reaction.

1 . A chemically activated thermal covering comprising: 
 a thermogenic system, comprising a compartment containing a first reagent maintained at a first pressure, an actuator for controllably isolating a second reagent from the first reagent, the second reagent maintained at a second higher pressure than that of the first reagent, and a channel for connecting the compartment to the actuator, whereupon the pressure differential between the first and second reagents draws the second reagent into the compartment; and    a foldable, conformable, generally planar carrier material for carrying the thermogenic system in the form of a covering.    
   
   
       2 . The covering of  claim 1  wherein the second reagent is contained within a dedicated reservoir.  
   
   
       3 . The covering of  claim 2  wherein the reservoir is volumetrically changeable.  
   
   
       4 . The covering of  claim 2  wherein the reservoir comprises an expandable bladder.  
   
   
       5 . The covering of  claim 1  wherein the reagents are selected to result in a cooling effect.  
   
   
       6 . The covering of  claim 1  wherein the reagents are selected to result in a heating effect.  
   
   
       7 . The covering of  claim 1  wherein the second reagent is obtained from an environment within which the covering is located.  
   
   
       8 . The covering of  claim 1  wherein the second reagent is oxygen contained within air.  
   
   
       9 . The covering of  claim 1  comprising a nonwoven fabric.  
   
   
       10 . The covering of  claim 1  comprising a surgical drape.  
   
   
       11 . The covering of  claim 1  comprising a blanket.  
   
   
       12 . The covering of  claim 1  wherein the thermogenic system comprises a conduit system having a plurality of compartments and channels.  
   
   
       13 . The covering of  claim 13  wherein each conduit system contains at least one channel leading to a plurality of compartments.  
   
   
       14 . The covering of  claim 1  wherein the thermogenic system comprises a bank of independently controllable actuators each capable of introducing a second reagent into a conduit system containing a channel connected to a compartment containing the first reagent.  
   
   
       15 . The covering of  claim 1  wherein the first reagent is impregnated within a foam.  
   
   
       16 . The covering of  claim 1  wherein the first reagent is impregnated within a sponge-like material.  
   
   
       17 . The covering of  claim 1  wherein the compartment is maintained under a vacuum until the actuator is actuated at which time the second reagent is drawn into the compartment initiating a thermal reaction.  
   
   
       18 . The covering of  claim 1  comprising a film layer.  
   
   
       19 . The covering of  claim 1  wherein the thermogenic system is affixed to an exterior surface of the carrier.  
   
   
       20 . The covering of  claim 1  wherein the channel comprises collapsible elastic tubing.