JPS63132136A - Rotary viscometer - Google Patents

Abstract

PURPOSE:To allow a detector mounted on a duct to sense the proximity of metallic member fixed to both end parts of an elastic member from the rotations of the metallic members and to detect the synchronous delay between a shaft and an internal cylinder and measure the viscosity of fluid by transmitting the constant-speed rotations of a motor to the internal cylinder in the fluid through the shaft and elastic member and generating torque proportional to the viscosity of the fluid. CONSTITUTION:The rotations of the synchronous motor 12 are reduced 13 in speed to a specific rotating speed and transmitted as a constant rotation output to the internal cylinder 3 through the watertight material 10 and elastic member 6 of the shaft 4. The internal cylinder 3 operates as a rotor to generate the viscosity torque of the fluid by the rotation of the peripheral surface. Stationary rotations are made in the state of rotary displacement to an angle where the torque and the reaction force of the elastic member 6 are balanced with each other. Further, an external cylinder 2 provided to a duct 1 cuts off the influence of the flow velocity of the fluid to the flank of the internal cylinder 3. The proximity of the 1st metallic member 7 and 2nd specific-angle metallic member 8 provided to both ends of the elastic member 6 is sensed to outputs the quantity of the rotary displacement proportional to the viscosity to the detector 11 as a time interval signal, thereby finding the viscosity from the quantity of the displacement from the relative position of the members 7 and 8.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is applicable to, for example, a rotational viscometer that measures the viscosity of a fluid;
In particular, it relates to continuous measurement of fluid viscosity in process plants and the like.

[Prior Art] FIG. 6 shows an example of an explanatory diagram of a conventional rotational viscometer, for example. In the figure, 1 is a pipe through which fluid flows, 5 is a wire that suspends and holds the viscosity measuring mechanism on a fixed part, 6 is an elastic member that balances the twist of the wire 5, 9-3 is a bearing, and 12 is a synchronous motor. 13 is a reducer that reduces the rotational speed of the motor 12; 14 is an output shaft of the reducer; 30 is a rotational displacement sensor that converts the amount of twist of the wire 5 into an electrical signal. 31 is a magnet that generates a magnetic force that transmits rotational torque into the pipe line 1; 32 is a rotor incorporating the magnet 31 to which the rotational motion of the magnet 31 is transmitted via the partition wall of the pipe line 1 by a method of magnetic coupling; , 33 is the motor 12
It is a holding rod that is connected to the case.

A conventional rotational viscometer is configured as described above, and the motor 1
A rotatable rotor 32 containing a magnet 31 disposed in the fluid flowing in the direction of the arrow in the pipe 1 by the magnetic force of the magnet 31 rotationally driven by the magnet 31 is rotated by two bearings 9.
-3 is a fulcrum, rotational movement is performed, viscous torque of the fluid is generated, and the reaction causes the motor 12 and the holding rod 3.
3 is rotated and displaced, causing twist in the wire 5. Since the amount of twist is balanced with the elastic member 6, the twist angle of the wire 5 is converted into an electrical signal using the rotational displacement sensor 30 and output.

As mentioned above, the viscosity of the fluid in the pipe line 1 is continuously output as an electrical signal.

FIG. 7 shows an example of an explanatory diagram of another conventional rotational viscometer, for example. In the figure, 1.12.13.30 are the same as those of the conventional rotational viscometer described above. 2 is the motor 1 in the fluid
2 is an outer cylinder that is driven and rotated; 3 is an inner cylinder that is arranged concentrically with the outer cylinder 2 and rotationally displaced by the rotation of the outer cylinder 2; 4 is a shaft that transmits the rotation of the motor 12; 10 is provided in the conduit 1; Rare axis 4
34 is a torque tube that holds the inner cylinder 3 to the conduit 1, and 35 is a connecting shaft whose one end is fitted into the inner cylinder 3 and transmits rotational displacement.

A conventional rotational viscometer is constructed as described above, and has a cantilever structure in which the double cylinders of the outer cylinder 2 and the inner cylinder @3 are opened at right angles to the flow direction in the pipe 1 through which the fluid flows in the direction of the arrow. It is located. The rotation speed of the motor] 2 is reduced by a reducer 13, and the outer cylinder 2 is directly immersed in the fluid flow in the conduit 1 by the shaft 4.
Rotate. The inner cylinder 3, which is located concentrically with the outer cylinder 2 and held by the torque tube 34 in the conduit 1, is rotationally displaced by the generation of viscous torque due to the rotation of the outer cylinder 2. The amount of displacement is determined by the viscosity of the inner cylinder 3. The rotation angle is such that the torque and the reaction force of the torque tube 34 are balanced, so that the rotational displacement of the inner cylinder 3 is transmitted to the rotational displacement sensor 30 via the connecting shaft 35, and the torque can be measured.

(Problems to be solved by the invention) In the rotational viscometer shown in the example of Fig. 6 above, the magnet 3
1 and employs a magnetic coupling method that utilizes its magnetic force, it cannot be applied to paints where the measuring fluid is a specific fluid, especially a magnetic tape containing a magnetic material. In addition, if the fluid contains iron as a contaminant, maintenance is required to remove the iron adhering to the rotor.

In the conventional viscometer shown in Fig. 7 above, the spring rigidity of the torque tube is large, so the viscous torque of the inner cylinder 3 is required to have a large value, and is suitable for measuring high viscosity fluids, but it is suitable for measuring low viscosity fluids. It is difficult to obtain the amount of displacement required by the displacement sensor 30.

Furthermore, recently, it has become necessary to measure at a sliding speed that is suitable for the location of use, so especially when low values of viscosity and sliding speed are required, the dimensions of the inner cylinder 3 or rotor 32 must be significantly large because the shear stress is small. It is not practical. There was a problem in that it was difficult to measure low viscosity at low shear rates using the torque tube 34.

This invention was made in order to solve such problems, and the purpose is to obtain a rotational viscometer that can secure a measurement range from low viscosity to high viscosity for fluids containing magnetic materials and various other fluids. do.

[Means for Solving the Problems] The rotational viscometer according to the present invention includes an outer cylinder having a circulation hole installed in a pipe through which a fluid flows, and a rotational viscometer that penetrates an airtight material provided in the pipe. The shaft for transmitting data to the inside is connected via an elastic member having elasticity in the direction of rotation, and the inner cylinder is arranged concentrically within the outer cylinder and has one end pivoted to the conduit, and the inner cylinder has a predetermined structure at both ends of the elastic member. A first metal member and a second metal member arranged at an angle, a detector attached to a conduit that senses the proximity of the metal members, and a bearing whose shaft slides at the center of the other end of the cylinder. It is.

[Operation] In the present invention, constant speed rotation of the motor is transmitted to the inner cylinder in the fluid via the shaft and the elastic member to generate a torque in the inner cylinder that is proportional to the viscosity of the fluid. The detector attached to the conduit is sensitive to the proximity of the metal member fixed to both ends of the elastic member by rotation, and the lag in synchronization between the shaft and the inner cylinder is detected without contact, and the viscosity can be measured.

[Embodiment] FIG. 1 is a sectional view showing an embodiment of the present invention, and in the figure, 1 to 4.6.10 and 12.13 are the same as those of the conventional device. 7 is a first metal member serving as an index of the rotational position of the shaft 4, 8 is a second metal member serving as an index of the rotational position of the inner cylinder 3, 9-1.9-2 is a bearing, and 11 is the proximity of the metal member. 1 shows a detector installed in the conduit 1 that outputs an electrical signal in response to the

In the rotational viscometer configured as described above, the rotation of the motor 12 using, for example, a synchronous motor is reduced to a predetermined rotation speed by the reducer 12, and the constant rotation output is transmitted through the pipe line 1 of the shaft 4.
It is transmitted to the inner cylinder 3 via the elastic member 6 through the airtight member 10 provided at the penetrating position. A shaft 4 is attached to the center of the upper surface of the inner cylinder 3.
The inner cylinder 3 acts as a rotor due to the bearing 9-1 which is pivotally supported by a pivot with low friction at the center of the lower surface of the inner cylinder 3, and the inner cylinder 3 acts as a rotor. Viscosity torque of the fluid is generated due to rotation, and this torque and the elastic member 6
Steady rotation is performed with the rotational displacement at an angle where the reaction force is balanced. The outer cylinder 2 provided in the pipe line 1 shields the influence of the flow velocity of the fluid on the side surface of the inner cylinder 3, so that the fluid to be measured does not remain between the outer cylinder 2 and the inner cylinder 3 and is constantly exchanged. It has a communication hole at the end of its circumferential surface.

The magnitude of the rotational displacement proportional to the viscosity is determined by a time interval signal sent to a detector 11 that is sensitive to the proximity of the first metal member 7 and the second metal member 8 provided at both ends of the elastic member 6 and forming a predetermined angle. occurs, and from the relative position signals of the first metal member 7 and the second metal member 8 that are settled when the rotating shaft 4 is stopped, the amount of displacement from the relative position signal during steady rotation is determined and converted into units. The viscosity is determined by this.

Note that at the start of detection of this amount of rotational displacement, the first metal member 7
It is necessary to distinguish between the metal member 8 and the second metal member 8, but the full-scale rotational displacement amount must be within 180°, and a gate signal with a 1/2 rotation period of the shaft 4 is provided, so that the metal member 8 is identified within the gate signal. It can be determined immediately after driving based on whether or not the detected signal is included.

The elastic member 6 has elasticity in the direction of rotation of the shaft 4, and can be, for example, a coil spring, a spiral spring, a torsion wire, or a leaf spring 16. By selecting the spring stiffness, low viscosity can be measured at a low shear rate. A predetermined amount of displacement can be secured even when the full-scale torque is small.

FIG. 2 shows an example of a top view of the inner cylinder, and shows a bearing 15 in which the shaft 4 is held by a plurality of holding rods provided at the center of the inner cylinder 3.
has been incorporated into.

FIG. 3 is a sectional view showing another embodiment of the present invention, and FIG. 4 is a top view showing an example of an elastic member in which a plurality of bent leaf springs 16 are used. In this example, a leaf spring 1 fitted to the shaft 4
The other end of the elastic member 6 is provided above the inner cylinder 3, but the structure in which the elastic member 6 is disposed between the shaft 4 and the inner cylinder 3 is the same as the embodiment shown in FIG. In this embodiment, the radial position restraining force of the inner cylinder 3 is reduced, but since the upper bearing 9-2 is not used, the effect of significantly reducing friction can be obtained.

If a high-frequency oscillation type proximity switch is used as an example of the detector 11, and the first metal member 7 and the second metal member 8 are arranged as detection parts of the proximity switch so as to form a small gap when approaching the proximity switch, it is possible to Since the switch outputs an electric signal in response to the proximity of each metal member during rotation, the time interval can be accurately measured without contact, and the amount of displacement can be determined.

In addition, if the fluid to be measured is not a magnetic fluid and does not contain impurities such as iron powder, the detector 11 detects the presence of ferromagnetic material in the first metal member 7 and the second metal member 8 using a proximity switch using a magnetoresistive element, for example. It can also be detected using In this case, the proximity switch can be used by being attached to the outer surface of the conduit 1 made of non-magnetic metal such as stainless steel.

FIG. 5 shows an example of measuring the viscosity of a fluid in a tank as another embodiment of the present invention. An outer tube 2 is used instead of the conduit 1 in FIG. Fix to form a predetermined angle.

Reference numeral 17 denotes a holding fitting 17 for holding the shaft 4 at the rotational center position of the inner cylinder 3, and a bearing 9-2 is provided at the center thereof. The viscosity of the fluid in the tank can be measured by installing the inner cylinder 3 in a position where it is reliably immersed in the fluid in the tank and rotating the shaft 4. There is a fluid flow inside the tank, and the fluid to be measured can be exchanged between the outer cylinder 2 and the inner cylinder 3 through the communication holes provided in the outer cylinder 2.

Furthermore, even when used in a sealed pressurized container, the components are not affected by the pressurizing force, so viscosity can be measured accurately.

In the present invention, a first metal member 7 and a second metal member 8 are arranged to form a predetermined angle at both ends of an elastic member 6 that rotationally drives an inner cylinder 3 that generates viscous torque in a fluid. The relative rotational position of the second metal member can be detected using a detector 11 that operates in a non-contact manner with respect to various fluids such as magnetic fluid, and furthermore, by selecting the spring stiffness of the elastic member 6, it is possible to measure particularly low viscosity. This allows for a wide measurement range up to high viscosities.

The center of rotation of the inner cylinder 3 is pivoted by the low-friction pivot of the bearing 9-1, and since no other sliding parts are used for signal conversion, the friction torque is extremely small and the viscosity can be adjusted with high precision. The inner cylinder 3 is connected to the bearing 9-2 and the shaft 4.
Since the center of rotation is held by the holding fitting 17, stable operation can be achieved with respect to photographing and mounting postures.

[Effects of the Invention] As explained above, the present invention transmits the rotation of the shaft via the elastic member to the inner cylinder arranged concentrically with the outer cylinder in the fluid,
A simple structure in which first and second metal members are provided at both ends of the elastic member to detect twisting caused by viscous torque in the inner cylinder, and a detector that is sensitive to the proximity of the metal members is provided, which allows for easy detection of fluid flow in process plants, etc. The viscosity of various fluids such as magnetic fluids in pipes and pressurized tanks can be measured continuously online. By selecting the spring stiffness of the elastic member, a measurement range from low to high viscosity can be secured. The center of rotation of the inner cylinder is held by a shaft and a bearing, so it is less affected by photography and mounting orientation, allowing continuous continuous measurement over a wide measurement range of viscosity with high accuracy and stability. There is an effect.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing one embodiment of the present invention, Fig. 2 is an example of an inward top view, Fig. 3 is a sectional view showing another embodiment of the invention, and Fig. 4 is an example of an elastic member. Top view showing 5th
FIG. 6 is a sectional view showing another embodiment of the present invention, FIG. 6 is an explanatory view showing a conventional rotational viscometer, and FIG. 7 is an explanatory view showing another conventional rotational viscometer. In the figure, 1 is a pipe, 2 is an outer cylinder, 3 is an inner cylinder, 4 is a shaft,
6 is an elastic member, 7 is a first metal member, 8 is a second metal member,
9-1.9-2 is a bearing, 10 is an airtight material, 11 is a detector,
12 is a motor, and 13 is a speed reducer. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (2)

[Claims] (1) An outer cylinder having a circulation hole installed in a pipe through which fluid flows, and a shaft that transmits rotation to the inside of the pipe through an airtight material provided in the pipe with elasticity in the direction of rotation. an inner cylinder that is coupled via an elastic member, is arranged concentrically within the outer cylinder, and has one end pivoted to the pipe; and a first cylinder that is arranged at a predetermined angle at both ends of the elastic member. It is characterized by comprising a metal member, a second metal member, a detector attached to the conduit that is sensitive to the proximity of the metal member, and a bearing provided at the center of the other end of the inner cylinder and on which the shaft slides. Rotational viscometer. (2) The rotational viscometer according to claim 1, characterized in that an elastic member is attached to the upper end of the inner cylinder and a shaft is fitted in the center.