On-gimbals cryogenic cooling system

Abstract

The present invention is a system for cryogenic cooling of an object mounted on gimbals. A transfer line made up of one or more flexible small diameter transfer tubes is used to connect the compressor, which is located separately from the gimbals, and the cryocooler, which is mounted on the gimbals in thermal contact with the object to be cooled. The transfer line of the system of the invention has a total gas transfer capacity equal to that of the large diameter lines used in conventional systems but allows essentially unhindered rotation of the gimbals yoke and platform about the gimbals' axes, under the influence of gravity or with the help of motors.

1 . A cryocooling system for cooling an object mounted on a gimbals platform, said system comprising:
 a. a gimbals fixed to a support;   b. a cryocooler mounted on the platform of said gimbals, and in thermal communication with said object;   c. a compressor located separately from said platform;   d. one or more internal conduits located at and coaxial with one or more of the rotational axes of said gimbals, for facilitating the passing of refrigerant from said compressor to said cryocooler;   e. a supply line for transferring said refrigerant from said compressor to said internal conduit; and,   f. a first transfer line for transferring said refrigerant from said internal conduit to said cryocooler;   
     wherein said first transfer line comprises two or more small diameter flexible tubes joined together in parallel at each of their ends by a connector. 
   
   
       2 . A system according to  claim 1 , wherein the small diameter tubes comprise an internal diameter of between 0.2 mm-0.3 mm. 
   
   
       3 . A system according to  claim 1 , wherein the small diameter tubes comprise a wall thickness of between 0.05 mm-0.15 mm. 
   
   
       4 . A system according to  claim 1 , wherein the tubes are made from any one of the materials selected from the group consisting of:
 a. stainless steel; and,   b. copper-nickel alloy.   
   
   
       5 . A system according to  claim 1 , further comprising:
 a. a second transfer line for transferring the refrigerant from the cryocooler to the internal conduit; and,   b. a return line for transferring said refrigerant from said internal conduit to the compressor;   
     wherein said second transfer line comprises two or more small diameter flexible tubes joined together in parallel at each of their ends by a connector 
   
   
       6 . A system according to  claim 1 , wherein the gimbals and the cryocooler are surrounded by a container having an outlet, and wherein said system further comprises a return line for transferring the refrigerant from said outlet to the compressor. 
   
   
       7 . A system according to  claim 1 , wherein the internal conduit is located at any one of the group consisting of:
 a. the gimbals z-axis;   b. the gimbals y-axis; and   c. the gimbals x-axis   
   
   
       8 . A system according to  claim 1 , wherein the internal conduit comprises any one of the group consisting of.
 a. a passage for refrigerant that is transferred to the cryocooler; and,   b. a passage for refrigerant that is transferred to the cryocooler, and a passage for refrigerant that is transferred from the cryocooler;   
   
   
       9 . A system according to  claim 1 , wherein the refrigerant comprises a mixture of gases. 
   
   
       10 . A system according to  claim 9 , wherein the refrigerant's maximum pressure is less than 3 MPa. 
   
   
       11 . A method for cooling an object mounted on a gimbals platform, by a cryocooling system, said method comprising the following steps:
 a. providing a cryocooling system comprising:
 i. a gimbals fixed to a support; 
 ii. a cryocooler mounted on the platform of said gimbals, and in thermal contact with said object; 
 iii. a compressor located separately from said platform; 
 iv. one or more internal conduits located at, and coaxial with, one or more of the rotational axes of said gimbals, for facilitating the passing of refrigerant from said compressor to said cryocooler; 
 v. a supply line for transferring a refrigerant from said compressor to said internal conduit; and, 
 vi. a first transfer line for transferring said refrigerant from said internal conduit to said cryocooler; 
   b. compressing said refrigerant to a predetermined pressure;   c. causing said refrigerant to flow from said supply line to said internal conduit;   d. causing said refrigerant to flow through said internal conduit to said first transfer line; and,   e. causing said refrigerant to flow through said first transfer line to said cryocooler, thereby cooling said object;   
     wherein said first transfer line comprises two or more small diameter flexible tubes joined together in parallel at each of their ends by a connector. 
   
   
       12 . A method according to  claim 11 , further comprising:
 a. causing the refrigerant to flow from the cryocooler through a second transfer line to the internal conduit;   b. causing said refrigerant to flow through said internal conduit to a return line; and,   c. causing said refrigerant to flow through said return line to the compressor;   
     wherein said second transfer line comprises two or more small diameter flexible tubes joined together in parallel at each of their ends by a connector. 
   
   
       13 . A method according to  claim 11 , further comprising:
 a. providing a container having an outlet, that surrounds the cryocooler and gimbals, into which the refrigerant flows from said cryocooler; and,   b. causing the refrigerant to flow from said outlet through a return line to the compressor.