Waters Technologies Corporation

Ta Instruments-Waters LLC

Waters Technologies Coproration

Nigel Doe

Peter Foster

Scott Merrullo

Described are a method and device for controlling a temperature of a sample. The sample may be a rheometer sample. A thermal control system comprising a geometry element, heat conductor element, heater element, cooling device and thermal resistance layer is used. The cooling device may be a Peltier element. The heat conductor element is disposed adjacent to and in thermal communication with the geometry element. The heater element is in thermal contact with the heat conductor element. The thermal resistance layer is disposed between and in thermal contact with an element surface of the heat conductor element and a cooling surface of the cooling device. The heater element is operated to cause heat to flow to the geometry element and the cooling device is operated to cool the cooling surface to a temperature that is less than a temperature of the element surface.

Rheometer having resistance heater and cooling device

A rotary rheometer includes a drive shaft and a dual read head optical encoder that is configured to measure angular displacement or angular velocity of the drive shaft.

Rotary rheometer with dual read head optical encoder

A rheometer includes a drive shaft, a drag cup motor for rotating the drive shaft, a first measuring object supported by the drive shaft, a second measuring object, a linear position sensor, and processing and control electronics. The linear position sensor includes a target (e.g., an aluminum target) mounted to the drive shaft, and a pair of coils. The linear position sensor is configured to measure thermal expansion of the drive shaft based on a change in impedance of the coils resulting from a displacement of the target relative to the coils. The processing and control electronics are in communication with the coils and are configured to adjust a position of one of the measuring objects relative to the other based on a change in impedance of the coils resulting from a displacement of the target relative to the coils, thereby to maintain a substantially constant measurement gap therebetween.

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Wilmington, DE, United States of America

Nigel Doe