TH112882A - Real-time viscosity measurement device while stirring - Google Patents

Abstract

The real-time agitator viscosity measurement device according to the present invention has the unique feature of not requiring a torque sensor, which is a major component of commonly used viscosity measurement devices. The shaft is cooled by arranging a set of cooling pipes with shaft sleeve and bearings as a single assembly, which eliminates friction in the rotating system from cooling with coolant, as the coolant does not directly contact the shaft. The impeller is suitable for mixing, the impeller surface is coated with heat-resistant and corrosion-resistant materials, and the viscosity value during agitation is displayed in real time using electrical power values from measuring the electric current and pressure drop across a servo DC electric motor at constant rotational speed, a condition where the viscosity of the liquid varies with the electrical power of the motor used to drive the impeller.

Claims (6)

All rights reserved, which will not appear on the advertisement page: 1. A real-time viscosity measurement device for agitated liquids, consisting of a vertical slide assembly (20) with a ruler (21) for measuring distance mounted on one part and a mounting base (19) on a portion of the vertical slide assembly, characterized by one end of the mounting base connected to a cooling assembly consisting of a cooling pipe (16), a shaft sleeve (3) and ball bearings (4), (5), wherein the cooling pipe (16) is a cylindrical tube enclosing the shaft sleeve (3), with the upper and lower ends of the shaft sleeve being fitted with ball bearings (4) and (5), respectively. The cooling pipe (16), enclosing the shaft sleeve (3), creates an internal cavity, which is open to the outside through openings (17) and (18). These openings serve as inlets and outlets for coolant used to cool the shaft (2). The coolant does not directly contact the shaft, but dissipates heat through the bearings (4) and (5) to the shaft sleeve. One end of the shaft (2) is connected to the impeller (1), which is coated with heat-resistant and corrosion-resistant material. The other end of the shaft is connected to the servo motor (6) shaft by a coupling (7). The motor has an encoder (22) assembled in it, which is connected to the control box (23) by electric cables (24). The control box is used to receive and display the measurement values, as well as transmit the measurement results to the computer screen (25) by signal cables (26). The servo motor (6) is mounted on the motor base (8). Screws (9), (10), (11), and (12) support the motor base (8) and connect it to the shaft base (13). The four set screws also adjust the distance and plane of the motor. To align the axles of the shaft (2) and the motor shaft (6), the motor base (8) and the shaft base (13) are plates with holes in the center for the shaft (2) and the motor shaft (6), and holes at the four corners for the screws (9), (10), (11), and (12). A sleeve (14) is welded to the underside of the shaft base (13) for fitting onto the shaft sleeve (3), and is fixed to the shaft sleeve with a worm screw (15). 2. A real-time agitated liquid viscosity measuring device according to claim 1, wherein the impeller (1) is replaceable. 3. A real-time agitated liquid viscosity measuring device according to claim 1, wherein the viscosity measurement and agitator of a low-temperature liquid can be used without turning on the coolant. 4. A real-time agitation liquid viscosity measuring device according to claim 1, wherein the absolute viscosity of the liquid can be measured by calibrating the measurement result with a known liquid viscosity at the same test conditions. 5. A real-time agitated liquid viscosity measuring device according to claim 1, wherein the impeller immersion distance in the liquid that minimizes mixing time is in the range of 0.3 - 0.4 and at a high impeller rotational speed. 6. A real-time agitated liquid viscosity measuring device according to claim 1, wherein the motor speed control to rotate at a constant rotational speed is achieved by means of pulse width modulation.