Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A rheometric system includes an optical encoder coupled to a rotating shaft and configured to detect a rotational position of the shaft with respect to a reference. The rotational information is forwarded to a program or memory. An optical rotation plate is mechanically fastenable to the rotating shaft. A laser is provided to probe optical properties of a fluid sample proximate to the optical rotation plate. The system includes a detector system for measuring laser light scattered or transmitted through the sample chamber. The detector system is coupled to a memory that stores optical data collected after light impinges on the optical plate. Experimental fluid sample optical data and background optical data are each stored as a data structure that creates a point by point map of rotational position of the sample plate with the optical data collected thereat.

Abstract: A method of calibrating the torque outputs of a rheometer by using a calibrating object with a certified moment of inertia, measuring the moment of inertia of the calibrating object using the rheometer, and calculating the torque adjustment factor by dividing the certified moment of inertia value by the measured moment of inertia value. The torque adjustment factor is applied to correct subsequent measurements of rheological properties conducted using the rheometer. The torque adjustment factor may be double-checked for reproducibility by measuring the moment of inertia of the calibrating object, correcting it with the torque adjustment factor, and comparing it with its certified moment of inertia value.

Abstract: A method of calibrating the torque outputs of a rheometer by using a calibrating object with a certified moment of inertia, measuring the moment of inertia of the calibrating object using the rheometer, and calculating the torque adjustment factor by dividing the certified moment of inertia value by the measured moment of inertia value. The torque adjustment factor is applied to correct subsequent measurements of rheological properties conducted using the rheometer. The torque adjustment factor may be double-checked for reproducibility by measuring the moment of inertia of the calibrating object, correcting it with the torque adjustment factor, and comparing it with its certified moment of inertia value.

Abstract: A rheometric system includes an optical encoder coupled to a rotating shaft and configured to detect a rotational position of the shaft with respect to a reference. The rotational information is forwarded to a program or memory. An optical rotation plate is mechanically fastenable to the rotating shaft. A laser is provided to probe optical properties of a fluid sample proximate to the optical rotation plate. The system includes a detector system for measuring laser light scattered or transmitted through the sample chamber. The detector system is coupled to a memory that stores optical data collected after light impinges on the optical plate. Experimental fluid sample optical data and background optical data are each stored as a data structure that creates a point by point map of rotational position of the sample plate with the optical data collected thereat.

Abstract: A rotary rheometer having a an upper heating/cooling assembly and a lower heating/cooling assembly located opposite one another opposite a sample gap. The lower heating/cooling assembly may comprise a Peltier heater and the upper heating/cooling assembly preferably comprises a heating element that mates with a heat spreader for heating and cooling the area above the sample and providing more uniform heating and cooling across the sample gap while also minimizing any chimney effect within the rheometer and/or providing heating/cooling capability that is insensitive to changes in the gap between an upper geometry and the lower heating/cooling assembly. The upper heating/cooling assembly may further comprise a cooling channel for cooling the upper heating/cooling assembly.

Abstract: A rotary rheometer having a magnetic thrust bearing. The thrust disk of the magnetic thrust bearing being situated between a pair of magnetic actuator assemblies and extending beyond the circumference of the actuator assemblies so as to encompass the magnetic flux lines generated by the actuator assemblies, thus minimizing likelihood of an undesirable preferential position or side load.

Abstract: A rotary rheometer having a magnetic thrust bearing. The thrust disk of the magnetic thrust bearing being situated between a pair of magnetic actuator assemblies and extending beyond the circumference of the actuator assemblies so as to encompass the magnetic flux lines generated by the actuator assemblies, thus minimizing likelihood of an undesirable preferential position or side load.

Abstract: A rotary rheometer having a magnetic thrust bearing. The thrust disk of the magnetic thrust bearing being situated between a pair of magnetic actuator assemblies and extending beyond the circumference of the actuator assemblies so as to encompass the magnetic flux lines generated by the actuator assemblies, thus minimizing likelihood of an undesirable preferential position or side load.

Abstract: A system and method for automatic identification of a detachable component of an instrument is disclosed. The detachable component includes a machine-readable device that contains information associated with the detachable component. The machine-readable device can be a bar code, a variable depth pattern, a magnetic stripe, or the like. The information contained within the machine-readable device can include one or more of serial number, type, material, dimensions, and calibration data of the detachable component. The instrument includes a reader that is configured to obtain the information from the machine-readable device.

Abstract: A rotary rheometer having a magnetic thrust bearing. The thrust disk of the magnetic thrust bearing being situated between a pair of magnetic actuator assemblies and extending beyond the circumference of the actuator assemblies so as to encompass the magnetic flux lines generated by the actuator assemblies, thus minimizing likelihood of an undesirable preferential position or side load.

Abstract: A rotary rheometer having a an upper heating/cooling assembly and a lower heating/cooling assembly located opposite one another opposite a sample gap. The lower heating/cooling assembly may comprise a Peltier heater and the upper heating/cooling assembly preferably comprises a heating element that mates with a heat spreader for heating and cooling the area above the sample and providing more uniform heating and cooling across the sample gap while also minimizing any chimney effect within the rheometer and/or providing heating/cooling capability that is insensitive to changes in the gap between an upper geometry and the lower heating/cooling assembly. The upper heating/cooling assembly may further comprise a cooling channel for cooling the upper heating/cooling assembly.

Abstract: Devices, systems and methods are disclosed for sensing the temperature of a drag cup within a motor of a rheometer. Such a device includes a coil in communication with a source of current and in close enough proximity to a drag cup such that the coil senses the temperature of the drag cup through fluctuations in electrical activity across the coil.