Abstract:
A system for preventing the formation of ice about a port to a contained cooling area. The system includes a support tube that is adapted to pass through the port in a wall that forms part of the cooling area. The support tube is further adapted to provide a passage into the cooling area for a conduit. The support tube is still further adapted to contain dry nitrogen to prevent the formation of ice around the port.

Description:
BACKGROUND  
       [0001]     Electronic equipment is typically tested before they are sold as a product in the environmental conditions the equipment is likely to encounter in use. For example, for electronic equipment that will encounter cold temperatures during use, the electronic equipment is typically exposed to similar cold temperatures or even more extreme cold temperatures to see how the equipment will perform. One method of testing electronic devices for performance in cold temperatures is with a thermal chamber that is able to provide long cold soak periods. With this type of arrangement, the electronic device is placed in the thermal chamber and activated while its performance is monitored. To activate the device, a cable powering the electronic device is typically passed through a port or hole in a wall of the thermal chamber. To prevent the cold air from escaping from the port of the thermal chamber, foam or clay is typically packed around the cable at the port. However, with this arrangement, when the chamber is cold for an extended period of time, ice will form around the cable port. As the ice is formed, the cables providing the power to the electronic device are stressed. The ice can also damage the cables insulation causing shorts. Moreover, as the ice melts when the chamber is warmed, the water will runs down the cables which may short out the power supply or the electronic device in the chamber.  
         [0002]     For the reasons stated above and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for a system and method of preventing the formation of ice around input/output (I/O) ports of a contained cooling system.  
       SUMMARY OF INVENTION  
       [0003]     The above-mentioned problems of current systems are addressed by embodiments of the present invention and will be understood by reading and studying the following specification.  
         [0004]     In one embodiment, an ice prevention system for a contained cooling area is provided. The system includes a support tube that is adapted to pass through a port in a wall that forms part of the cooling area. The support tube is further adapted to provide a passage into the cooling area for a conduit. The support tube is still further adapted to contain dry nitrogen to prevent the formation of ice around the port.  
         [0005]     In yet another embodiment, a method of preventing ice from forming near a port of a contained cooling system is provided. The method includes maintaining an amount of dry nitrogen near the port.  
         [0006]     In still another embodiment, a method of forming an ice prevention device around a port to contained cooling area is provided. The method includes positioning a support tube through the port so that a first end of the support tube is positioned in the contained cooling area and a second end is outside the contained cooling area. Capping the first and second ends of the support tube. Positioning a conduit through the support tube and providing a dry nitrogen input to the support tube.  
         [0007]     In further another embodiment, an ice prevention system is provided. The system includes a means to contain an amount of dry nitrogen about a port to a contained cooling system. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]     The present invention can be more easily understood and further advantages and uses thereof more readily apparent, when considered in view of the description of the preferred embodiments and the following figures in which:  
         [0009]      FIG. 1  is a cross-sectional diagram of a ice prevention system for a thermal chamber of one embodiment of the present invention;  
         [0010]      FIG. 2  is a flow diagram illustrating one method of forming a ice prevention system of one embodiment of the present invention; and  
         [0011]      FIG. 3  is a flow diagram illustrating one method of operating an ice prevention system of one embodiment of the present invention. 
     
    
       [0012]     In accordance with common practice, the various described features are not drawn to scale but are drawn to emphasize specific features relevant to the present invention. Reference characters denote like elements throughout Figures and text.  
       DETAILED DESCRIPTION  
       [0013]     In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the inventions may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that logical, mechanical and electrical changes may be made without departing from the spirit and scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the claims and equivalents thereof.  
         [0014]     Embodiments of the present invention provide a system to prevent ice from forming around (near) ports into a contained cooling area such as a thermal chamber. The present invention places an amount of dry nitrogen around the ports into the contained cooling area thereby replacing moisture in air around the ports. Without the moisture, ice cannot form. Moreover, in embodiments of the present invention, the dry nitrogen is at room temperature which helps warm conduits (such as electrical cables, hydraulic lines and the like) before they exit the system and are exposed to normal atmospheric conditions.  
         [0015]     Referring to  FIG. 1 , a cross-sectional view illustrating an ice prevention system  100  of one embodiment of the present invention is provided. This ice prevention system  100  is used in conjunction with a thermal chamber  122  in this embodiment. This is by way of example and not by way of limitation. The ice prevention system  100  and methods described in this specification can be used on any contained cooling area. The ice prevention system  100  includes a support tube  102 . The support tube  102  is positioned through a port  124  (or aperture) in a wall of the thermal chamber  122 . As illustrated, a first end  109  of the support tube  102  is located in the thermal chamber  122  and a second end  111  of the support tube is located outside the thermal chamber  122 . The first end  109  of the support tube  102  is capped with a first boot  108 . Likewise, the second end  111  of the support tube  102  is capped with a second boot  110 . In one embodiment, the first and second boots  108  and  111  are secured to the first and second ends  109  and  111  of the support tube  102  via clamps  112  and  114 .  
         [0016]     An inlet  104  is provided on the support tube  102  to selectively allow dry nitrogen to be introduced into an interior chamber  103  formed by the support tube  102  and the first and second boots  108  and  110 . Moreover in one embodiment, an outlet  103  is used to allow dry nitrogen to flow out of the interior chamber  103  of the support tube. Further in one embodiment, the outlet  106  is a solenoid adapted to expel the dry nitrogen when a pressure in the interior chamber  103  reaches a select level.  
         [0017]     As illustrated in  FIG. 1 , a conduit  120  is passed through a first boot aperture  115  in the first boot  108  and a second boot aperture  117  in the second boot  110 . Accordingly, the conduit  120  passes through the support tube  102  and the port  124 . As discussed above, the conduit can be any type of delivery system or a tube that carries power or an agent like a hydraulic fluid or the like to activate a device under test. In one embodiment, a first clamp  116  is used to secure a portion of the first boot  108  around the conduit  120  and a second clamp is used to secure a portion of the second boot around the conduit  120 . In embodiments, of the present invention, a seal created by the first and second clamps around the conduit  120  is not air tight. That is, in embodiments of the present invention, small amounts of dry nitrogen are allowed to escape out of the interior chamber  103  where the conduit is coupled to the respective first and second boots  108  and  110 . This helps prevent moisture in air from getting near the port  124 . Moreover, in one embodiment, the amount of dry nitrogen leaking out from by conduit-second boot seal that is outside the chamber is greater than the amount of dry nitrogen leaking into the thermal chamber from the conduit-second boot seal  
         [0018]     A method of forming an ice prevention system of one embodiment of the present invention is illustrated in  FIG. 2 . As illustrated in  FIG. 2 , a support tube  102  is positioned through a port  124  of a contained cooling area  122  ( 202 ). The support tube  102  is designed to fit snuggly in the port  124  and have a first end  109  positioned inside the contained cooling area  122  and a second end  111  outside the contained cooling area. Although, the support tube  102  is illustrated as being tubular is shape, it will be understood in the art the support tube  102  can have any shape. The only limitation is that a portion of the support tube  102  must fit snuggly through the port  124 . In one embodiment the support tube  102  is made out of a PVC pipe. Ends of the support tube  102  are then capped ( 204 ) and ( 206 ). In one embodiment, the support tube  102  is capped with boots made of a pliable material like rubber or the like. In one embodiment, the boots  108  and  110  are attached to respective ends of the support tube with clamps  112  and  114 . The boots  108  and  110  each have an aperture (first boot aperture  115  and second boot aperture  117 ) in which a conduit  120  is passed through ( 208 ). Hence, the conduit  120  passes through the support tube  102  and the port  124 . As discussed above, the boots  108  and  110  are coupled to the conduit  120  about the apertures  115  and  117 . In one embodiment this is accomplished with clamps  116  and  118  that allow a certain amount of the dry nitrogen to leek between the apertures  115  and  117  and the conduit  120 .  
         [0019]     Referring to  FIG. 3 a  flow diagram illustrating one method of using an ice preventing device of the present invention is provided. As illustrated, this method begins by directing a flow of dry nitrogen into an input  104  of a support tube  102 . This provides an amount of dry nitrogen around the port  124  of the contained cooling area  122 . In one embodiment, a select amount of dry nitrogen is allowed to leak out of the internal chamber  103  about at least one connection between the first and second boot apertures  115  and  117  and the conduit  120  ( 304 ). This helps keep air with moisture away from the port area. Moreover, in one embodiment, a larger flow of dry nitrogen is leaked out of the second boot aperture-conduit connection than the first boot aperture-conduit connection.  
         [0020]     In the embodiment illustrated in  FIG. 3 , the pressure in the interior chamber  103  is monitored ( 306 ). In one embodiment this is done with a solenoid that is designed to open at a select pressure to release the gas. It is then determined if the pressure exceeds a desired pressure ( 308 ). If the pressure exceeds the desired pressure ( 308 ), a flow of dry nitrogen is released from outlet  106  in the support tube  102 . If the pressure does not exceed the desired pressure ( 308 ), the pressure is continued to be monitored at ( 306 ). The desired pressure in the interior chamber  103  in one embodiment of the present invention is about 1 to 2 PSI.  
         [0021]     Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement, which is calculated to achieve the same purpose, may be substituted for the specific embodiment shown. This application is intended to cover any adaptations or variations of the present invention. Therefore, it is manifestly intended that this invention be limited only by the claims and the equivalents thereof.