Apparatus for cryosubstitution or low-temperature substitution

Abstract

An apparatus for cryosubstitution or low-temperature substitution is disclosed. The apparatus encompasses a Dewar vessel ( 1 ) that is embodied with a neck. A chamber ( 5 ) for reception of at least one specimen is inserted in the neck ( 5 3 ). The chamber ( 5 ) is embodied with a heavy base ( 5 1 ) that is connected to a first thermal conduction rod ( 7 ). A platform ( 8 ) is provided at the end of the first thermal conduction rod ( 7 ) facing away from the base ( 5 1 ). An insulator ( 12 ) is provided above the platform ( 8 ) of the first thermal conduction rod ( 7 ).

1 . An apparatus for cryosubstitution or low-temperature substitution comprises: a Dewar vessel that is embodied with a neck and is filled with a liquid coolant, a chamber for reception of at least one specimen wherein the chamber is inserted in the neck, a heavy base is provided to the chamber wherein the heavy base of the chamber is connected to a first thermal conduction rod that is connected, at the end facing away from the base to a platform; and the thermal conduction rod is equipped, above the platform, with an insulator.  
   
   
       2 . The apparatus according to  claim 1 , wherein the liquid coolant is liquid nitrogen.  
   
   
       3 . The apparatus according to  claim 1 , wherein the first thermal conduction rod and the platform are embodied integrally.  
   
   
       4 . The apparatus according to  claim 1 , wherein a second thermal conduction rod is connected to the first thermal conduction rod.  
   
   
       5 . The apparatus according to  claim 4  wherein the second thermal conduction rod is connected at one end to a platform; the end of the second thermal conduction rod located opposite to the platform is connected to the platform of the first thermal conduction rod; and the platform is directed toward a receptacle embodied at the base of the Dewar vessel.  
   
   
       6 . The apparatus according to  claim 5 , wherein the platform of the second thermal conduction rod is in contact with the receptacle.  
   
   
       7 . The apparatus according to  claim 5 , wherein the platform of the second thermal conduction rod is pot-shaped and fits around the receptacle.  
   
   
       8 . The apparatus according to  claim 4 , wherein the second thermal conduction rod is surrounded, above the platform, by an insulator.  
   
   
       9 . The apparatus according to  claim 1 , wherein at least one heating element and at least one temperature sensor are recessed into the base of the chamber; and the heating element and temperature sensor are connected to an electronic control system.  
   
   
       10 . The apparatus according to  claim 9 , wherein the base of the chamber is connectable to an annular plate; the at least one heating element is recessed into this plate, the at least one temperature sensor being recessed into the base of the chamber or into the annular plate.  
   
   
       11 . The apparatus according to  claim 9 , wherein the temperature sensor is embodied as a thermocouple or as a resistance temperature sensor; and its temperature signal serves as a controlled variable for the electronic control system in order to control the chamber temperature.  
   
   
       12 . The apparatus according to  claim 1 , wherein a further heating element, which preferably is electrically operated, is immersed in the liquid nitrogen in order to vaporize additional liquid nitrogen so that the cold gas cools the platform of the first cooling rod.  
   
   
       13 . The apparatus according to  claim 1 , wherein at least one sensor is provided which ascertains the fill level of the liquid nitrogen in the Dewar vessel.  
   
   
       14 . The apparatus according to  claim 13 , wherein the at least one sensor is a temperature sensor that is connected to the electronic control system in order to measure the fill level.  
   
   
       15 . The apparatus according to  claim 14 , wherein several temperature sensors are provided which are arranged along the first and the second thermal conduction rod.  
   
   
       16 . The apparatus according to  claim 5 , wherein the liquid coolant is liquid nitrogen and at least one of the insulators of the first or the second thermal conduction rod is embodied as a tube that is immovably adhesively bonded to the corresponding platform so that the thermal conduction rod is insulated with respect to the liquid nitrogen.  
   
   
       17 . The apparatus according to  claim 16 , wherein a pump is provided which pumps the liquid nitrogen into at least one of the tubes that surround the first and/or the second thermal conduction rod.  
   
   
       18 . The apparatus according to  claim 17 , wherein the pump is embodied as a membrane pump having a membrane and ball valves.  
   
   
       19 . The apparatus according to  claim 18 , wherein the pump is divided, so that the membrane is arranged outside the Dewar vessel and the ball valves provided in a valve head are arranged inside the Dewar vessel.  
   
   
       20 . The apparatus according to  claim 1 , wherein the insulator that is not embodied as a tube is an insulating foam.