Temperature control apparatus with recirculated coolant

A workstation with a temperature control for adjusting the temperature of the workstation and a work medium at the workstation to a predetermined temperature, comprising:

• a workstation,
• a source of fluid coolant,
• a cooling vehicle, main coolant temperature sensor and main coolant temperature control for detecting and maintaining the temperature of the fluid coolant at a temperature below said predetermined temperature,
• a flow line, a return line, and a recirculating pump for receiving fluid coolant from said source of fluid coolant and providing fluid coolant to the workstation and producing cooling of the workstation and work medium therein,
• a workstation temperature sensor and workstation temperature control for detecting and regulating the temperature of the workstation,
• a coolant heater in said flow line responsive to said workstation temperature control for heating the coolant being supplied to the workstation to a temperature nearly equal to said predetermined temperature as to maintain the workstation and work medium at said predetermined temperature,
• said workstation temperature control reducing the heating by said heater while a substantial differential exists between the workstation temperature and said predetermined temperature, and said workstation temperature control increasing the heating by said heater as said differential decreases and as the workstation temperature nearly achieves said predetermined temperature,
• a flow regulator in said flow line for maintaining the desired rate of flow of coolant through said flow line, and
• a bypass valve for bypassing both said heater and said flow regulator, thereby providing a flow of unwarmed coolant to the workstation at an increased rate of flow, said bypass valve being responsive to said workstation temperature control.