Constant cooling circuit and system

A circuit for monitoring the heat dissipation capacity of a cooling medium, comprising:

• a bridge circuit;
• one leg of said bridge circuit including a temperature-sensitive resistance set to balance the bridge at a predetermined temperature and heat dissipation level of said temperature-sensitive resistance when immersed in the medium whose heat dissipation capacity is to be monitored;
• and
• means, responsive to a bridge imbalance resulting from a change in heat dissipation capacity of the medium, for varying current flow to said bridge to return said temperature-sensitive resistance to said predetermined temperature and heat dissipation level and re-balance the bridge at a different voltage level, the difference in voltage between the first bridge balance level and the second bridge balance level representing the cooling medium heat dissipation adjustment required to maintain said temperature-sensitive resistance at said predetermined temperature and heat dissipation level.

A system for maintaining a cooling medium at a constant heat dissipation capacity, comprising:

• means for defining the initial heat dissipation capacity of the cooling medium by imparting a first level of power to a temperature-sensitive element immered in the cooling medium to maintain the temperature of said element at a predetermined temperature;
• means for sensing a change in temperature of said element;
• means, responsive to said means for sensing, for restoring the temperature of said element to said predetermined temperature by altering the power imparted to said element until said predetermined temperature is achieved at a second level of power;
• means, responsive to said means for restoring, for indicating the differential in power, required to return the element to said predetermined temperature, representative of the corresponding change in the heat dissipation capacity of the medium;
• and
• means, responsive to said means for indicating, for modifying the heat dissipation capacity of the medium return the medium to said initial heat dissipation capacity.