Method of determining measurement data of samples and rheometer

Patent metadata

Field	Value
Publication number	US-9574983-B2
Application number	US-201514627166-A
Country	US
Kind code	B2
Filing date	Feb 20, 2015
Priority date	Feb 20, 2014
Publication date	Feb 21, 2017
Grant date	Feb 21, 2017

Abstract

A method determines measurement data of samples by using a rotation rheometer and a linear DM(T)A analysis unit. The rotation rheometer has units for measuring and/or adjusting the normal force exerted by or on the measurement shaft and/or the speed, deflection angle and/or torque of the measurement shaft. The linear DM(T)A analysis unit has units for measuring the tensile and/or pressure force and/or the position and/or the feed movement of its adjustment rod. The sample to be examined is arranged between opposite measurement parts. Accordingly, the rotational forces or torques transmitted via the sample from the measurement shaft to the adjusting rod, when obtaining measurement data with the linear DM(T)A analysis unit, and, when obtaining measurement data by the rotation rheometer, for the tensile or pressure forces or linear adjustment forces transmitted via the sample from the adjustment rod to the measurement shaft are compensated for.

First claim

The invention claimed is:

1. A method for determining measurement data of samples, which comprises the steps of:
providing a rotation rheometer and a linear DM(T)A analysis unit, the rotation rheometer having units for measuring and/or adjusting a normal force exerted by or on a measurement shaft and at least one of a speed, a deflection angle or a torque of the measurement shaft, the linear DM(T)A analysis unit having an adjustment rod and units for measuring at least one of a tensile force, a pressure force, a position or a feed movement of the adjustment rod, the measurement shaft of the rotation rheometer being rotatably mounted in a bearing, and the adjustment rod of the linear DM(T)A analysis unit being linearly movably mounted in a further bearing;
disposing a sample to be examined between opposite measurement parts including a first measurement part supported by the measurement shaft and a second measurement part supported by the adjustment rod; and
compensating for rotational forces or torques transmitted via the sample from the measurement shaft of the rotation rheometer to the adjusting rod of the linear DM(T)A analysis unit, when obtaining measurement data with the linear DM(T)A analysis unit, and, when obtaining measurement data by the rotation rheometer, for the tensile force, the pressure force or linear adjustment forces transmitted via the sample from the adjustment rod to the measurement shaft during a determination and/or analysis of the measurement data.

2. The method according to claim 1 , which further comprises during the determination of the measurement data, the rotation rheometer and the DM(T)A analysis unit are started together, and the measurement data of the sample are obtained with the rotation rheometer and the DM(T)A analysis unit either alternating one immediately after the other or simultaneously.

3. The method according to claim 1 , wherein if the measurement data are obtained with the rotation rheometer effects of the adjustment rod on the measurement shaft in a direction of a feed axis of the adjustment rod are compensated for by maintaining the measurement shaft and/or the measurement component supported by the measurement shaft is kept at a constant height relative to a reference point determined on the rotation rheometer, or for the linear adjustment forces and resultant movements exerted on the measurement component of the adjustment rod are compensated mathematically during the analysis of the measurement data.

4. The method according to claim 1 , wherein during the determination of the measurement data with the DM(T)A analysis unit effects of the torques exerted by the measurement shaft on the adjustment rod are compensated for by keeping the adjustment rod and/or the measurement part rotationally invariant, or by mathematically compensating for the rotational forces exerted on the measurement part by the measurement shaft and resultant movements during the analysis of the measurement data.

5. The method according to claim 1 , which further comprises compensating for at least one of periodic movements or periodic forces of the adjustment rod and the measurement shaft on one another with at least one of counter movements or counter forces occurring at same intervals.

6. The method according to claim 1 , wherein the measurement part supported by the adjustment rod and the measurement shaft abut one another without pressure or at a specified pressure, and specified linear movements of the adjustment rod and/or rotational movements of the measurement shaft necessary for measurements to be carried out, and the forces, the pressures, or the torques occurring between the measurement shaft and the adjustment rod and vice versa, and resultant movements and/or changes in movement are recorded and made available for calibrations during the determination of the measurement data for mathematical compensation.

7. The method according to claim 1 , wherein during the determination of the measurement data, the forces exerted by the adjustment rod via the sample on the measurement shaft, and vice versa, and resultant movements and/or changes in movement are continuously sensed and determined, and used for an immediate exertion of counter forces, counter torques, and/or the induction of counter movements on the adjustment rod and/or the measurement shaft compensate the forces and movements and/or changes in movement of the adjustment rod and/or the measurement shaft.

8. The method according to claim 1 , wherein a stiffness of the bearing of the measurement shaft is increased or adjusted relative to a height adjustment relative to a base and/or by adjusting or increasing a stiffness of the further bearing of the adjustment rod relative to a rotation around a feed axis in order to compensate.

9. The method according to claim 1 , wherein to compensate for the forces exerted by the adjustment rod, a height of the measurement part supported by the measurement shaft is kept at a specified level or specified distance from a base relative to the base specified on the rotation rheometer.

10. The method according to claim 1 , which further comprises:
determining adjustment forces exerted by the adjustment rod on the measurement shaft via a normal force measurement unit provided in the rotation rheometer and for readings of the adjustment forces to be provided to a compensation unit to adjust a height of the measurement shaft or the measurement part, an adjustment unit and/or the DM(T)A analysis unit contains a further compensation unit controlling a unit that rotates the adjustment rod and turns the adjustment rod depending on signals provided by a sensor that determines a rotational position of the adjustment rod.

11. The method according to claim 1 , wherein the measurement shaft with the measurement part and any measurement motor driving the measurement shaft are mounted together on a support opposite a specified base on the rheometer with an adjustment drive so as to allow for height adjustments, and the adjustment drive is provided with adjustment signals depending on the pressure forces exerted by the adjustment rod on the measurement shaft, thus adjusting the height of the support.

12. The method according to claim 1 , wherein the DM(T)A analysis unit is rotatably mounted relative to a base about an adjustment axis of the adjustment rod with a rotation drive, a compensation unit controls the rotation drive, and the DM(T)A analysis unit, depending on the rotational forces exerted by the measurement shaft on the adjustment rod, rotates the DM(T)A analysis device in order to compensate for the forces or the torques.

13. A rheometer for determining rheometric measurement data, the rheometer comprising:
a rotation rheometer having a bearing, a measurement part, a measurement shaft and units for at least one of measuring normal forces, adjusting the normal forces, measuring a speed of said measurement part, measuring a torque exerted by said measurement shaft or on said measurement shaft, or measuring an angle of deflection of said measurement shaft, said measurement shaft is rotatably mounted in said bearing;
a linear DM(T)A analysis unit having an adjustment rod, a further measurement part, a further bearing, a linearly adjustable adjustment rod guided in said further bearing, and units for at least one of measuring tensile forces, measuring pressure forces, determining a position of said adjustment rod, and determining a feed movement of said adjustment rod, said further measurement part and said measurement part forming a measurement gap and a sample to be examined is inserted into said measurement gap; and
at least one compensation unit, by which rotatio

Assignees

• Anton Paar Gmbh

Inventors

• Santner Friedrich

Classifications

• G01N2011/0006

  Calibrating, controlling or cleaning viscometers · CPC title

• G01N11/14 Primary

  by using rotary bodies, e.g. vane (G01N11/16 takes precedence) · CPC title

• G01N11/142

  Sample held between two members substantially perpendicular to axis of rotation, e.g. parallel plate viscometer · CPC title