JP3068987B2 - Rotary viscometer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an economical method of converting a viscosity finger detection result of a rotary viscometer into an electric signal. The present invention relates to improvement of a rotary viscometer using a transit time pulse counting signal conversion method.

[0002]

2. Description of the Related Art In a chemical industry, a synthetic science industry, a pharmaceutical industry, a food industry, an oil and fat industry, a paint industry, a textile industry, a cosmetics industry, and the like, a liquid material is used as a main raw material or an auxiliary raw material. 2. Description of the Related Art Various rotary viscometers are widely used for reaction control and quality control when a product is manufactured by processing.

The measurement principle of this rotary viscometer will be described with reference to FIG. FIG. 1 illustrates the above-described application.
The measurement principle of a rotary viscometer (for example, a B-type viscometer) that is currently most frequently used will be described.

As shown in FIG. 1, a conventional viscometer mainly has a variable speed motor 1 as a rotary driving source.
And an output shaft 2 connected to the variable speed motor 1 and a scale disk 3 engraved with an angle scale 3a 'through which the output shaft 2 is fixed. Further, the viscometer includes a spring 4 attached to the lower end 2 'of the output shaft 2, a rotor stem 5 attached to the lower end of the spring 4, and a measured object attached to the lower end of the rotor stem 5. It includes a cylindrical rotor 7 immersed in the liquid 6 and a U-shaped pointer 8 provided on the upper end of the rotor stem 5. Here, the U-shaped pointer 8
Is mounted so that it can point to the angle scale 3a 'on the scale disk 3.

In this conventional viscometer, the cylindrical rotor 7 is
It is immersed in the liquid to be measured 6 whose viscosity is to be measured. In this state, when the variable speed motor 1 is rotated at a constant speed, the spring 4 is twisted to an angle balanced with the viscosity torque of the liquid 6 to be measured generated in the cylindrical rotor 7. Spring 4 at this time
Since the torsional angle of the liquid 6 and the viscosity of the liquid 6 to be measured are in a proportional relationship, the viscosity of the liquid 6 to be measured is obtained by reading the scale plate finger 3a 'indicated by the tip 8a of the U-shaped pointer 8. be able to.

Here, in order to obtain a measured value, the finger index 3a 'on the scale plate 3 must be read while the scale plate 3 is rotating. In general, the upper limit of the number of rotations of the scale plate 3 is about 60 rpm, so that it is not impossible to visually read the finger strength, but it is extremely inconvenient, and there has been a need for improvement since ancient times. Further, recently, there have been demands for functions related to automation, such as remote control of a viscometer, automatic measurement, and automatic recording of measurement results. Therefore, it is becoming impossible to cope with the conventional visual reading of the pointer finger.

For this reason, the pointer finger 3 on the scale disk 3
a ′, that is, the torsion angle of the spring 4 is transmitted as an electric signal using a signal converter that directly converts the angle into an electric signal, such as a rotary differential transformer or a rotary encoder, Viscometers of an automatic reading system for displaying or recording an index by receiving this signal with a suitable receiver have already been put to practical use in expensive rotary viscometers such as rheometers.

However, these signal converters have a complicated structure and are expensive in cost, and have a drawback that they cannot be used for a low-cost on-site rotary viscometer.

In view of such a situation, the present inventor has applied for an invention relating to a viscometer provided with an automatic reading device for a scale plate as shown in FIG. 2 (Japanese Patent Application No. 49-1).
No. 11236). The automatic reading device listed here is based on the principle of measuring the passing time difference between the pointer rotating in the viscosity measurement state and the zero point of the scale disk, and the operation is stable and cost effective. Due to its low cost, it is still widely used in relatively inexpensive rotary viscometers (for example, E-type viscometers).

FIG. 2 shows the structure of the reader according to the prior art. This reading device is connected to a variable speed motor 1 and driven to rotate, a scale plate 3 attached to the drive shaft 12, and connected to a rotor 7. For the resistance torque, a spiral spring type torque spring (not shown) has a torque detection shaft 15 for detecting a twist angle generated by balancing, and a pointer 8 fixed to the torque detection shaft 15.

Further, this reading apparatus includes two sets of optical detectors 200 and 210 each composed of a light emitting diode 16 and a phototransistor 17, a light shielding piece 3a provided on the lower surface of the scale plate 3, and a pointer 8. And a light shielding piece 8a fixedly provided.

The optical detector 200 has a light shielding piece 3a provided on the lower surface of the scale plate 3, and the optical detector 210 has
A light-shielding piece 8a fixed to the pointer 8 detects light-shielding when passing through a gap between the light-emitting diode 16 and the photo-transistor 17 together with rotation of the drive shaft 12 and the torque detection shaft 15 of the viscometer.

Furthermore, in this reading device, the rotor 7
When the viscometer is operating in a state where the viscous resistance torque of the liquid 6 to be measured is not applied to the torque detection shaft 15 via the torque detector 15, the optical detectors 200 and 210 simultaneously operate the respective light shielding pieces 3a and 8a. Positioned and mounted to detect passage.

If the relative positions of the optical detectors 200 and 210 are determined in advance as described above, when the viscosity is measured by immersing the rotor 7 in the liquid 6 to be measured, the optical detector 200 is used.
And 210 detect the passage of the light shielding pieces 3a and 8a, respectively, corresponding to the torsional angles in rotation of the drive shaft 12 and the torque detection shaft 15.

The torsional angular displacement of the torque spring caused by the viscous resistance torque of the rotor 7 is, as shown in the upper two stages of FIG. 3, a pulse signal from the phototransistor 16 of each of the optical detectors 200 and 210. It appears as the phase difference θ of the transmitted pulse signal.

Accordingly, in order to automatically read the pointer index of the viscometer, for example, as shown in the lower part of FIG. 3, signals from two phototransistors 16 are used as gate signals.
In response to the rotation speed of the drive shaft 12 output during that time,
A clock pulse having a predetermined oscillation frequency is counted.

If the transmission frequency of the pulse is related to the rotation speed of the drive shaft 12 in advance, the counted number of pulses corresponds to the torsion angle. The automatic reading equivalent to the reading of the pointer finger can be performed.

This prior art is a method in which the difference between the transit time between the pointer 8 and the scale disk 3 is counted by a clock pulse to make the measured value correspond to the scale index.
In addition, there is a feature of stable operation at low cost.

[0019]

However, in the prior art, one rotation of the scale plate 3 of the rotary viscometer per rotation.
The reading can be performed only once. Therefore, when the viscometer is operated at a low rotation speed such as 0.5 rpm, for example, in the worst case, the first measurement data cannot be obtained unless the user has to wait two minutes after the start of operation. Furthermore, after that, 2
There is an inconvenience that the finger reading is performed only once per minute.

Further, in the case of such a signal conversion system having a low data density, for the purpose of measurement requiring a viscosity measurement value immediately after the start of viscosity measurement, for example, a two-liquid curing reaction speed is high. When the curing time characteristic of a mixed adhesive or the like is measured as a change in viscosity, there is a problem that the measurement cannot be performed at all.

It is an object of the present invention to provide a rotary viscometer capable of reading a finger a plurality of times during one rotation of a drive shaft of the viscometer.

[0022]

Means for Solving the Problems To solve the above problems ,
According to the present invention, the rotating rotor is immersed in the liquid to be measured.
By measuring the viscosity of the liquid to be measured,
The torque detection shaft connected to the rotor and the rotating drive
A drive source, a drive shaft driven by a rotary drive source, and a drive
An elastic member that elastically connects the shaft and the torque detection shaft,
Multiple rotations of the drive shaft for one predetermined rotation
First rotation detecting means for outputting a detection signal in units of angle
And the rotation of the torque detection shaft to one predetermined rotation
Output a detection signal in multiple angle units
Rotation detection means and detection from the first and second rotation detection means.
Receiving the output signal, detecting those time intervals, and
And a viscosity index calculating means for obtaining the viscosity index corresponding to the distance.
A rotary viscometer is provided. Concrete
Specifically, for example, the problem is to immerse a rotating rotor in a liquid to be measured, in a rotary viscometer that measures the viscosity of the liquid to be measured, a torque detection shaft connected to the rotor, and a rotation drive source. A drive shaft driven by a rotary drive source, an elastic member for elastically connecting the drive shaft and the torque detection shaft, and a detection signal for rotation of the drive shaft in a predetermined angle unit of 180 ° or less. The first rotation detecting means for outputting and the rotation of the torque detecting shaft are determined by a predetermined 18
A second rotation detecting means for outputting a detection signal in an angle unit of 0 ° or less, and a time difference detecting means for taking in output signals from the first and second rotation detecting means and detecting a time interval between them. From the detected time interval, having a finger reading means for calculating a viscosity finger corresponding to the rotational phase difference between the drive shaft and the torque detection shaft,
This can be achieved by a rotary viscometer.

[0023]

In the rotary viscometer to which the present invention is applied, the drive shaft is rotated at a constant speed by the rotary drive source while the rotor is immersed in the liquid to be measured for viscosity. Then, the elastic member is twisted to an angle at which the viscous torque of the liquid to be measured generated in the rotor and the elastic force of the elastic member connecting the torque detection shaft and the drive shaft connected to the rotor are balanced. A phase difference occurs in the rotation of the shaft. At this time, since the twist angle of the elastic member and the viscosity of the liquid to be measured are in a proportional relationship, the viscosity of the liquid to be measured can be obtained by detecting the viscosity index corresponding to the twist angle.

In the present invention, the rotational phase difference corresponding to the viscosity index is converted into a signal as described below, and the viscosity index is automatically detected.

When the drive shaft rotates, the first rotation detecting means outputs a signal for each predetermined angle unit. Also,
At the same time, the second rotation detecting means also outputs a signal for each rotation of the torque detection shaft for each predetermined angle unit. Here, since the angle unit is 180 ° or less, the signal is output two or more times during one rotation of the drive shaft or the torque detection shaft. In addition, since a phase difference corresponding to the torsion angle occurs in the rotation between the drive shaft and the torque detection shaft, these two signals are output with a time lag.

The time difference detecting means detects the time interval between the two signals outputted by the first and second rotation detecting means a plurality of times during one rotation. The finger degree reading means calculates the viscosity finger degree corresponding to the twist angle from the detected time interval each time the time interval is input from the time difference detection means.

Therefore, according to the present invention, the viscosity index can be calculated a plurality of times during one rotation of the drive shaft or the torque detection shaft according to a predetermined angle unit of 180 ° or less.

[0028]

FIG. 4 shows an embodiment of a viscometer to which the present invention is applied.
This will be described with reference to FIG. In the following description, the same reference numerals in the drawings denote the same parts.

This embodiment measures the viscosity according to the measurement principle described with reference to FIG. 1, and has a functional block shown in FIG.

In this embodiment, as shown in FIG. 9, a cylindrical rotor 7 for detecting the viscosity of the liquid 6 to be measured, a drive mechanism 110 as a rotary drive source, a torque detecting shaft connected to the cylindrical rotor 7 and A rotation mechanism 100 having a drive shaft that is rotationally driven by the drive mechanism 110, a phase difference detection mechanism 120 that converts and detects a rotation phase difference between two axes included in the rotation mechanism 100 into an electric signal, and a phase difference detection mechanism 120
A controller 130 for calculating the viscosity index of the liquid 6 to be measured and controlling the driving mechanism 110 using the signal regarding the phase difference output from
And a rotation number setting unit 150 for setting various constants such as the rotation number of the driving source in the driving mechanism 110.

The cylindrical rotor 7 is used to detect the viscosity.
It is immersed in the liquid 6 to be measured. Here, the cylindrical rotor 7 is used, but a conical rotor or the like may be used.

The structure of the driving mechanism 110 will be described with reference to FIG. FIG. 6 is a side view of the present embodiment, showing an outline of the internal structure of a drive system mounted on the upper part.

As shown in FIG. 6, the driving mechanism 110
A driving pulse motor 21, a driving timing pulley 22 attached to an output shaft thereof, a timing belt 24 wound around the pulley 22, and a driving shaft (hereinafter referred to as a rotating main shaft) driven to rotate by the timing belt 24. ) 25 and a pulley 23 attached to the pulley 23. Further, although not shown, the driving mechanism 110
A power supply device for the pulse motor 21 is included.

As the driving pulse motor 21, a pulse motor having a small basic step angle is used to ensure smooth rotation which is important as a viscometer. Furthermore, a multi-step speed change can be electronically performed by using a micro-step drive system in which the number of divisions is appropriately increased.

The structure of the rotation mechanism 100 will be described with reference to FIG. FIG. 7 is a schematic sectional view of the internal structure of the viscometer of the present embodiment shown in FIG. 6 as viewed from the front.

As shown in FIG. 7, the rotation mechanism 100 has
A hollow rotary spindle 25 driven by a pulse motor 21 (see FIG. 6) via a pulley 23 and the like; bearings 26a and 26b rotatably supporting the rotary spindle 25 at two upper and lower ends thereof; A first U-shaped connecting member 27 attached to the lowermost end of the rotating main shaft 25;

The rotating mechanism 100 further includes a jewel bearing 28 provided on the lower side 27a of the first U-shaped connecting member 27, and a pivot 3 supported by the jewel bearing 28.
0, a torque detecting shaft 29 having a pivot 30 implanted at its lower end, a second U-shaped connecting member 27b connected to the torque detecting shaft 29 above the pivot 30,
And a torque detecting shaft connecting member 29a provided below the U-shaped connecting member 27b and connected to the cylindrical rotor 7 via the rotor stem 5.

Here, the torque detecting shaft 29 penetrates inside the hollow rotary main shaft 25 without contacting each other, and extends upward.

The configuration of the phase difference detection mechanism 120 of this embodiment will be described with reference to FIG. FIG. 8 shows the phase difference detection mechanism 1.
FIG. 2 is a schematic view of the present embodiment, including parts directly related to 20.

The phase difference detecting mechanism 120 is provided with a U-shaped arm member 31 attached to the upper end of the hollow rotary main shaft 25 and an upper side 31a of the U-shaped arm member 31 coaxially with the rotary main shaft 25. A cup-shaped steady rest 32 having a small hole 32a on the bottom surface, a pin 33 inserted through the small hole 32a and implanted in the upper end surface 29b of the torque detecting shaft 29, and attached near the upper end of the torque detecting shaft 29. And a torque spring 34 in the form of a spiral spring.

Here, the outer peripheral winding end of the torque spring 34 is locked to the inside 31 b of the U-shaped arm member 31.
In addition, the steady rest 32 and the pin 33 function as a bearing for stopping the radial swing of the torque detecting shaft 29.

Further, the phase difference detecting mechanism 120 has a rotating shaft shielding disk 35 attached above the rotating shaft 25 and below the U-shaped arm member 31, and a pin implanted at the upper end of the torque detecting shaft 29. It includes a torque detection shaft shielding disk 36 attached to the disk 33, and optical detectors 200 and 210 provided on the respective shielding disks 35 and 36 for detecting passage of a slit described below.

Each of the optical detectors 200 and 210 comprises a light emitting diode 16, a light receiving element phototransistor 17, and a power supply control device (not shown) necessary for them. Light emitting diode 16 and light receiving element photo
The transistor 17 is a shield disk 35, 36, respectively.
Are provided facing each other up and down.

The shielding disks 35 and 36 are the same, and a slit 300 is provided at a position where the entire circumference is equally divided as shown in FIG. In this embodiment, the shielding disk 3
It is assumed that slits for transmitting light are provided at positions 5 and 36 at every 72 ° where 360 ° is divided into five equal parts. of course,
The number of divisions in the shielding disks 35 and 36, that is, the number of slits is not limited to this.

Also, instead of the light transmission slit 300,
As an index, a reflector that reflects light, a small piece of a magnetic member, or the like can be used. However, in this case, it is necessary to use a detector for each index according to the characteristics of each index.

Instead of using the shielding disks 35 and 36, an index may be directly attached to the shaft surface of the rotating main shaft 25 and the torque detecting shaft 29, or a cylinder fixed to each shaft may be used.

Shielding disks 35 and 36 and optical detector 2
00 and 210 respectively correspond to the cylindrical rotor 7
Is rotating with no load, the optical detector 2
00 detects the passage of one of the light transmitting slits 300 of the disk 35 and the optical detector 210
The position at which the passage through any one of the light transmission slits 300 is detected is the same as the position at which the passage is detected.

The controller 130 of this embodiment has
As shown in the figure, a clock circuit 131 for generating a clock pulse of a predetermined frequency, a counter 133 for counting inputted pulses, and optical detectors 200 and 21
A gate circuit 132 that controls the output of an input clock pulse using the passage detection pulse from 0 as a gate signal.
And the number of pulses calculated by the counter and the pulse motor 21
And a pulse motor driver 135 for calculating the viscosity fingeriness of the liquid 6 to be measured from the rotation speed of the liquid.

Here, the pulse motor driver 135 is
A motor drive signal corresponding to the designated number of revolutions is given to the pulse motor 21 of the drive mechanism 110 by the signal of the number of revolutions setter 150 to control the rotational motion. In addition, the clock circuit 131 generates a clock pulse having an oscillation frequency corresponding to the rotation speed and given by the following equation 2 by the same signal as the rotation speed designation signal sent to the pulse motor 21.

As shown in FIG. 9, the display 140 displays the viscosity index of the liquid to be measured, which is output from the controller 130. Further, the viscosity index output from the controller 130 may be directly output as data for external viscosity calculation.

According to the present embodiment having the above-described structure, it is possible to detect the viscosity index five times during substantially one rotation of the cylindrical rotor 7. However, in the specification of the present embodiment, it is required that the viscosity measurement data obtained by the viscometer of the present invention be the same as the viscosity measurement data obtained by the conventional viscometer, that is, that the continuity of the measurement be ensured. . Therefore, the structural specifications necessary to ensure this continuity will be examined.

As in the present embodiment, almost one of the cylindrical rotors 7
In order to allow five readings during rotation, the light transmission slit 30 is divided every 72 ° by dividing 360 ° of the shielding plate into five.
In addition to providing 0, the spring constant of the torque spring 34 is considered to match the condition of the spring constant used in the conventional viscometer. Need to be reviewed.

That is, in the conventional viscometer, the spring constant of the torque spring 34 is related to generate a full-scale torque for a twist angle of 315 °. Therefore, in the case of 5 divisions and 72 ° in this embodiment,
It is necessary to change the spring constant of the torque spring 34 to 5.25 (= 315 ° / 60 °) times the conventional spring constant so that a full-scale torque is generated when the torsion angle is 60 °.

The reason why 60 ° corresponds to the twist angle at which full-scale torque is generated without using the entire range of the angle range of 72 ° is that an angle margin is required for the work of adjusting the viscometer. Of course, it is sufficiently possible to reduce the angle of the margin to 65 ° or 70 ° as the full-scale torque, except for the difficulty of the adjusting operation at the time of adjusting the viscometer due to the narrow margin area.

Further, the frequency of the clock pulse is set such that the scale division specification of the scale plate 3 (see FIG. 2) of the conventional B-type or E-type viscometer is 100% full within a range of 315 ° of 360 °. 100 scales are engraved as a scale. Therefore, the oscillation frequency f ₀ of the clock pulse
Is to read 1 scale in this case to 1/10,

[0056]

(Equation 1)

Can be expressed as follows. Here, n is the rotational speed of the viscometer (rpm).

Therefore, considering data compatibility with such a conventional viscometer, in the present embodiment, the transmission frequency of the clock circuit 131 is such that when the angular range of 60 ° is selected as the full-scale torque range. It is necessary to determine that this angle of 60 ° corresponds to 100% of the full scale of the finger index as a viscometer. In this case, the clock frequency is

[0059]

(Equation 2)

Must be used. Here, n is the rotational speed of the viscometer (rpm).

The operation of the present embodiment will be described below with reference to FIGS. In the rotary viscometer of this embodiment, as shown in FIG. 6, the cylindrical rotor 7 is immersed in a liquid to be measured (not shown) whose viscosity is to be measured. In this state, when the pulse motor 21 is rotated at a constant speed, the rotating main shaft 25 is driven via the pulleys 22 and 23 and the timing belt 24.

When the rotating main shaft 25 rotates, as shown in FIG. 8, the rotating main shaft 25, the torque detecting shaft 29 connected by the torque spring 34, and the cylindrical rotor 7 rotate. Here, due to the viscous torque of the liquid to be measured, the torque spring 34 is moved to an angle that balances the viscous torque.
Is twisted. At this time, the torsion angle of the torque spring 34 and the viscosity of the liquid to be measured are in a proportional relationship.

In the present invention, this twist angle is detected by an optical detector which detects the passage of the light through the light-transmitting slit 300 by sandwiching the shielding disks 35 and 36 connected to the rotating main shaft 25 and the torque detecting shaft 29, respectively. 200 and 210.

The rotating main shaft 25 and the torque detecting shaft 29 are
When each rotates, the shielding disks 35 and 36 rotate.
According to the rotation of the disks 35, 36, the optical detectors 200, 210 each composed of the light emitting diode 16 and the phototransistor 17 arranged vertically with the light emitting axis and the light receiving axis interposed therebetween are formed by a light transmitting slit. Each time 300 passes through each detection point, it emits a pulse signal.

Here, a state in which the cylindrical rotor 7 is idled in the air (a completely unloaded state in which no load torque is applied to the cylindrical rotor 7), that is, a state in which the torque spring 34 is rotating without being subjected to torsion. FIG. 5 shows a time chart of the transmission pulses of the optical detectors 200 and 210 provided on the rotary shaft shielding disk 35 and the torque detection shaft shielding disk 36 in FIG.

In this embodiment, as shown in FIG.
In the no-load state, the light transmission slits 300 (A, BE) of the drive shaft shielding disk 35 and the light transmission slits 300 (A ′,
B'-E ') are the respective optical detectors 200, 21
0 at the same time, so that any light transmission slits 300 are arranged in such a way that no transit time difference occurs.

When measuring the viscosity using this example,
That is, when a viscous torque is applied to the cylindrical rotor 7 and the torque spring 34 rotates while being twisted, the outputs of the optical detectors 200 and 210 are as shown in the upper two stages in FIG. Here, any of the light transmission slits 300
Also, the time difference between the passage of the light transmission slit 300 of the rotary spindle shielding disk 35 and the passage of the light transmission slit 300 of the torque detection shaft shielding disk 36 is the same as described in the section of the prior art. It is proportional to the torsion angle of the torque spring 34.

However, unlike the prior art, in the viscometer of the present invention, the number of times corresponding to the number of light transmitting slits 300 obtained by dividing 360 ° of the shielding plate per one rotation of the cylindrical rotor 7 of the viscometer (number of the viscometers). (5 times in the embodiment).

The outputs from the optical detectors 200 and 210 are input as a gate signal to a gate circuit 132 shown in FIG. In this gate circuit 132,
Is received from the clock circuit 131 and the clock pulse output to the counter 133 is controlled by a gate signal.

Specifically, the gate circuit 132
As shown in FIG. 1, first, the output of the passage detection signal of each light transmission slit 300 from the optical detector 200 (FIG. 1)
0, at the time of receiving the pulses A, B to E), the output of the clock pulse received from the clock circuit 131 to the counter 133 is started. Next, the gate circuit 1
32 is a light transmission slit 30 from the optical detector 210.
When an output signal (pulse A ′, B ′ to E ′ in the middle part of FIG. 10) indicating the detection of the passage of 0 is input, the output of the clock pulse is stopped (the bottom part in FIG. 10).

The counter 133 counts a group of clock pulses output as described above. Here, the clock pulse has a fixed relationship with the rotation speed of the drive shaft as shown in Expression 2. Therefore, using this relationship,
The finger degree calculation unit 134 can easily calculate the twist angle or the viscosity finger degree from the count value and display the twist angle or the viscosity finger degree on the display 140.

In the present embodiment, the fingeriness calculation unit 134 calculates the viscosity fingeriness. However, it is also possible to finally calculate the viscosity based on the data of the viscosity finger degree in the finger degree calculation unit 134 and display the result on the display 140.

As described above, in the conventional viscometer,
While the scale reading could be performed only once per rotation of the scale plate, in the present embodiment, the viscosity index is increased by the number of light transmission slits 300 dividing the entire circumference per substantially rotation of the cylindrical rotor 7. Can be read. Therefore, if the number of light transmission slits is N, the time required for reading and displaying the first measured value and the time required for reading and displaying the measured value thereafter are reduced to 1 / N of the conventional viscometer. be able to. Even when the viscosity of the sample liquid changes in a short time, the number of measurements during one rotation of the viscometer can be measured at a density several times higher than that of the conventional viscometer. Can be enough.

[0074]

According to the present invention, in the viscosity measurement, the number of times of measurement during one rotation of the rotor for measuring the viscosity can be increased several times as compared with the conventional viscometer. Therefore, the time until the data is displayed at the low-speed rotation can be reduced to a fraction of that in the related art.

[0075]

[Brief description of the drawings]

FIG. 1 is a diagram showing the principle of a conventional rotary viscometer.

FIG. 2 is a view for explaining a pointer finger reading unit of a rotary viscometer according to a conventional technique.

FIG. 3 is a diagram showing outputs from optical detectors 200 and 210.

FIG. 4 is a view showing a shielding disk used in the embodiment of FIG. 9 to which the present invention is applied.

FIG. 5 is a diagram showing timings of output signals of two optical detectors in an unloaded state according to an embodiment to which the present invention is applied.

FIG. 6 is a side view of an embodiment to which the present invention is applied, showing a schematic configuration of a driving mechanism provided at an upper portion.

FIG. 7 is a front sectional view of the embodiment of FIG. 6, showing a schematic configuration of a rotation mechanism.

FIG. 8 is a diagram illustrating a schematic configuration of a phase difference detection mechanism according to the embodiment of FIG. 6;

FIG. 9 is a functional block diagram of an embodiment to which the present invention is applied.

FIG. 10 shows a state in which the viscosity is measured in the embodiment of FIG.
The figure which shows the timing of the output signal of two optical detectors.

[Explanation of symbols]

1: Variable speed motor, 2: Output shaft, 3: Scale disk, 3:
a ': Angle scale, 3a light shielding piece, 4 ... spring, 5 ...
Rotor stem, 6 ... sample liquid, 7: cylindrical rotor, 8: U-shaped pointer, 8a: light shielding piece, 12: drive shaft, 15: torque detection shaft, 16: light emitting diode, 17: phototransistor, 21 ... Driving pulse motor, 22, 23 pulley, 24 timing belt, 25 rotating spindle, 26a
26b: bearing, 27: first U-shaped connecting member,
27b: first U-shaped connecting member, 28: jewel bearing,
29: torque detection shaft, 29a: torque detection shaft connecting member,
Reference numeral 30: pivot, 31: U-shaped arm member, 32: steady rest, 33: pin, 34: torque spring, 35:
Rotating main shaft shielding disk, 36 ... Torque detection shaft shielding disk, 10
0: rotation mechanism, 110: drive mechanism, 120: phase difference detection mechanism, 130: controller, 131: clock circuit,
132 gate circuit, 133 counter, 134 finger calculation unit, 140 display unit, 150 rotation speed setting unit, 20
0, 210: Optical detector, 300: Light transmission slit.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-149841 (JP, A) JP-A-61-149842 (JP, A) JP-A-61-149843 (JP, A) JP-A-3-3 44535 (JP, A) Japanese Utility Model Showa 59-113746 (JP, U) Japanese Utility Model Showa 61-112255 (JP, U) Japanese Patent Publication No. 42-16033 (JP, B1) (58) Field surveyed (Int. ⁷ , DB name) G01N 11/00-11/16

Claims (7)

(57) [Claims] The method according to claim 1] immersing the rotor to rotate target solution, in a rotary viscometer measuring the viscosity of a test liquid, and the torque detection shaft coupled to the rotor, a rotary drive source, the rotary drive a drive shaft driven by the source, and the torque detection shaft and the drive shaft, and an elastic member for elastically connecting, for rotation of said drive shaft, a first for outputting a detection signal a plurality of times in one rotation a rotation detecting means, the rotation of the torque detection shaft, a second rotation detecting means for outputting a detection <br/> output signals a plurality of times in one rotation, from said first and said second rotation detection means receiving a detection signal when, detected their time interval, it is said detected
The drive shaft or the torque
A viscosity finger calculating means for calculating a plurality of viscosity finger degree for each rotation of the click detection axis of the drive shaft or the torque detection axis
For each rotation, the viscosity index is presented to the user multiple times.
Output means for outputting information for the rotation detection , wherein the first and second rotation detection means output
Signals are assigned to multiple rotation angles
What is output for each of the divided angle ranges
A is, each divided angular range, the elastic member is a full-scale preparative
An angle range equal to or more than the angle at which the torque is generated, and the viscosity index calculating means newly calculates
A rotary viscometer characterized by finding a suitable viscosity index . 2. The rotary viscometer according to claim 1, wherein each of the divided angle ranges is obtained by equally dividing the entire circumference.
Angle range, and the elastic member generates full-scale torque.
A margin angle for adjusting the measurement range is added to the resulting angle.
A rotary viscometer characterized by the following. 3. A rotary viscometer according to claim 1, wherein said viscosity index calculating means is provided with a signal from said first rotation detecting means.
After receiving the detection signal from the second rotation detecting means.
The time interval until the detection signal is received is determined by the full-scale
In the time unit set according to the angle at which the torque
Therefore, it must be measured and detected as a time difference.
Characteristic rotary viscometer. 4. The rotary viscometer according to claim 3, wherein said first and second rotation detecting means are provided on said drive shaft.
And optically detecting the rotation of the torque shaft.
The viscosity difference calculating means is used for detecting the time difference.
The time unit is that the elastic member generates full-scale torque.
The angle range of less than 1% of the angle
Rotary viscometer characterized by the following. 5. A rotary viscometer according to claim 3, wherein said viscosity index calculating means continuously transmits a clock pulse having a predetermined transmission frequency.
A clock circuit for detecting the rotation of the first rotation detecting means.
After receiving the output signal, detection from the second rotation detecting means
Generated by the clock circuit until the signal is received
A gate circuit for passing the clock pulse, and counting the clock pulse output from the gate circuit.
A counter for obtaining a signal indicating the time difference.
And a rotary viscometer. 6. The rotary viscometer according to claim 5, further comprising a rotation speed setting device for setting a rotation speed of said drive shaft.
The clock circuit is set by the rotation speed setting device.
Corresponding to the full-scale torque corresponding to the rotation speed n
Clock pulse multiplied by a constant determined by the angle
And a clock pulse counted in the counter
A rotary viscometer characterized by being produced. 7. The rotary viscometer according to claim 1, wherein said rotor is not immersed in a liquid to be measured and said rotor is not loaded.
When the drive shaft is driven, the first and second rotations are performed.
The rotation detecting means is configured to output a detection signal at the same time.
A rotary viscometer.