JPH0255933A - Viscometer - Google Patents

Abstract

PURPOSE:To automatically perform the measurement of a wide range by connecting plural measuring parts in parallel. CONSTITUTION:Viscosity substance fed to a supply means 3 with fixed quantity from a viscosity substance supply means 2 consisting of a casing 2a, a hopper 2b, a screw 2c and a supply path 2d is fed to any of fixed quantity measurement parts 4a-4c from a discharging port 32. If the quantity of fixed feeding quantity is taken as Q, the interior diameter and the length of a capillary part as (d) and L and pressure difference between the entrance and the exit of the capillary part as DELTAP, a share rate gamma and viscosity eta are expressed in formulas, so that the share rate gamma and the viscosity eta can be obtained by detecting the pressure of the entrance and the exit by pressure gauges 12 and 13. Since the interior diameter (d) of the capillary parts of the measurement parts 4a-4c is changed, the measurement of the wide range can be automatically performed when the viscosity substance is supplied by being switched with valves 4g-4j and the quantity of fixed feeding quantity Q is changed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention is utilized in the technical field of viscosity meters, and particularly relates to capillary type viscometers.

(Prior Art) As is well known, the relationship between the viscosity of a viscous material and the shear η is an important factor that affects the flow pattern and heat generation. That is, the flow state of the molten synthetic resin, for example, in a mold is influenced by the above-mentioned T~η characteristics, and it is necessary to know the T~η characteristics of the synthetic resin used when designing a mold. Furthermore, on the production line, it is necessary to measure the characteristic values of the synthetic resin that is actually flowing and perform quality control.

Typical and well-known viscometers for the above-mentioned purposes include a conical type, a capillary type, and a double cylinder type.

In the cone method, a solid synthetic resin plate shaped to fit the shape and size of this gap is placed between the cone surface and the bottom of a cone with an extremely small angle of inclination, and the cone is rotated by heating and melting it. It measures the torque during rotation. In the capillary method, a cylinder is used as a metered supply means, and a pellet or powder of solid synthetic resin is placed in the cylinder and heated and melted.By pushing a piston at a set speed, the melt is supplied from the capillary. It measures by extruding synthetic resin. In addition, in the double cylinder method, a solid synthetic resin is placed in the outer cylinder, heated and melted, and then the inner cylinder is immersed in the outer cylinder, and the outer cylinder is rotated. It measures torque.

On the other hand, in order to sufficiently maintain data on a wide variety of synthetic resins T~η, it is necessary to be able to measure easily not only in laboratories but also in factories. Although it is desired to develop a small and inexpensive viscometer that can perform measurements almost completely automatically, from this point of view, the above-mentioned viscometer has the following drawbacks.

(1) These viscometers use a batch method in which a fixed amount of solid synthetic resin is loaded into the measuring section, heated and melted, and then measured, so the material to be measured may change, or even if the material is the same. If there is more than a certain amount of time until the next measurement (for example, one day or more), the troublesome work of disassembling and cleaning the measurement part is required.

In the double cylinder method, there is a method of making the outer cylinder used for loading the sample disposable, but this also requires the work of removing, attaching, and reheating the outer cylinder, which is the sample loading part, and cannot be fully automated. sea bream.

In particular, when filling a sample with the capillary method, it is necessary to fill the sample little by little while compacting it to prevent air from entering the sample, which requires a hot wire.

(2) In order to measure all of the measurement ranges displayed in the catalog with these measuring instruments, it is necessary to switch the range used regardless of the method, and a special mechanism is required. .

In other words, in the capillary method, the range is switched by varying the speed of the sample passing through the capillary, but since there is a limit to the cylinder volume, that is, the amount of extrusion, the number of switching speed stages is limited, and t can be set to a wide range. In order to vary within the range, it is necessary to change the capillary. That is, when measuring section j over a wide range of t, it is necessary to clean the sample filling section and replace the capillary as the sample is refilled.

(3) Regarding the viscometer that solved each of the above-mentioned problems, the applicant of this invention previously applied for patent application No. 63-12247.
No. 5 (May 19, 1988) was filed (hereinafter referred to as the Hikari application).

However, in the viscometer of the previous application, a plurality of nozzles (capillary portions) of different diameters are connected in series to the quantitative supply means, so the total pressure drop due to these nozzles becomes excessive. Therefore, the quantitative supply means and the viscous material supply means connected upstream thereof must maintain a considerably high pressure with respect to atmospheric pressure, and the pressure is higher as the upstream side of the nozzles connected in series must be robustly constructed to withstand If the number of nozzles of different diameters connected in series is kept to a small number, it is possible to vary the quantity of fixed quantity supplied by the fixed quantity supply means over a wide range, but it is also possible to vary the quantity supplied by one fixed quantity supply means over a wide range. teeth,
Measurement accuracy is poor (not practical) because the supply amount is unstable.

(Problems to be Solved by the Invention) The problems to be solved by the present invention are the following problems in conventional viscometers as described above.

(1) Measurement work is difficult to be completely automated.

(2) To measure the entire range, it is necessary to replace the measurement range switching mechanism and the capillary.

(3) It must have a strong structure.

(Means for solving the problem) The viscometer 1 in the first invention of this invention is
This will be explained with reference to the figures.

The viscometer 1 of the present invention includes a viscous material supply means 2, a quantitative supply means 3 connected to the viscous material supply means 2, and a plurality of measurement units 4a, 4b, 4 connected to the quantitative supply means 3.
cm---, and each of these measurement units 4a, 4b4c
m--1 are connected in parallel to the quantitative supply means 3 via switching valves 4g, 4h, 4J--1, respectively, and each measuring section 4n, 4b, 4cm-- is provided with its inner diameter. Different capillary parts 41B, 42a, 41b, 42
1), it is a capillary type equipped with 41C142C.

Next, the viscometer 1 in the second invention is shown in FIG.
3b-1-- have different supply amounts, and the switching valve 4
g, and the measuring section 4 is selectively connected to the quantitative supply means 3a3b by switching the switching valve 4g.

(Function) In the viscometer 1 of the first and second inventions, the viscous material supply means 2 feeds the viscous material to the quantitative supply means 3.

In the first invention, the quantitative supply means 3 or the measuring sections 4a, 4b, 4cm-1 connected thereto are supplied. And fixed amount feed amount vQ of fixed amount supply means 3
, the inner diameter yd and length of the capillary part of any of the above measurement parts are L, and the pressure difference between the population outlets of the capillary part is △P,
Then, as is well known, T=f(Q, d)...
・・・・・・・・・・・・(1) η=f(Q, ΔP, L, d
)......T and η can be determined from the relational expression (2).

Further measurements i4a 4b 40...
Since the inner diameter of the capillary part is changing, the switching valve 4g
, 4h, 4j--1, the measuring section 4a4
In addition to obtaining the measured values for the number of capillaries attached to 4 cm, it is also possible to continuously measure a wider range by slightly changing the quantitative feed amount Q.

In the second invention, the quantitative supply means includes 3a, 3
b-m- and its fixed supply amount are different, and the switching valve 4g
By switching the measurement unit 4, the quantitative supply means 3a,
3b--- is selectively connected to one of them. Then, the viscous material flows into the measurement section 4 in a fixed quantity supplied by the selected fixed quantity supply means.

From the quantitative feed iQ and other factors at that time, do the same as above↑
, η are calculated. And quantitative supply means 3a, 3b--
In addition to obtaining as many measured values as possible, measurements can be made over a wider range by slightly changing the feed amount of each quantitative supply means 3a, 3b.

(Example) In the viscous material supply means 2, a screw 2c is fitted into a cylindrical casing 2a with a hopper 2b opened at the top. At the bottom of the casing 2a, the output shaft of the motor 6 is connected to the input shaft of the reducer 50 by the coupling 1. For example, a worm gear reducer is used as the reducer 5, and its output shaft is connected to the screw 2C to drive it in the direction indicated by the arrow in the figure.

Further, the viscous material supply means 2 is provided with heaters 2e, 2" and a thermometer 14.15m. A pressure gauge 11 is also provided in the supply path 2d.

Quantitative supply means 3, such as a gear pump, are used,
The suction port 31 is connected to the supply path 2d, and the discharge port 32 is connected to the measurement section 4.
is connected to. A variable speed motor 8 is provided to drive the quantitative supply means 3, and the output shaft of this motor 8 is connected to the drive shaft of the quantitative supply means 3 by a coupling 9.

Note that the motor 8 is provided with a tachometer 88.

As the metering supply means 3, a gear pump is preferable because it is small and precise, but other types of metering type pumps may be used.

In the embodiment of the first invention, the measuring sections 4a, 4b, and 4c are all constructed by connecting capillary sections with different inner diameters in series, as shown in FIG. That is, the measurement section 4a has capillary sections 41a and 42a, the measurement section 4b has capillary sections 41b and 42b, and the measurement section 4C has capillary sections 41a and 42a.
It has a capillary part of 1C42C, and the inner diameter of each capillary part is 41B, 42&, 41b, 42b, 4142
They are formed to have small diameters in order of dl, d2, d8, d4, d5, and d6.

A is provided with a first pressure gauge connection chamber 41 on its inlet side, and a pressure gauge 12 and a thermometer 16 are connected to this first pressure gauge connection chamber 43C.

The first pressure gauge connection chamber 43Q and the second pressure gauge connection chamber 43d
A capillary portion 41a is connected between the pressure gauge 13 and the temperature gauge 17 in the second pressure gauge connection chamber 43d.
is connected. Note that one end of the capillary portion 42B is connected to the second pressure gauge connection chamber 43d, and the other end is open to the atmosphere. Therefore, the pressure difference P with respect to the capillary portion 41B is the difference in reading between the pressure gauges 12 and 13, and the pressure difference Δ゛P2 with respect to the capillary portion 42B is the difference between the reading of the pressure gauge 13 and the atmospheric pressure.

In this embodiment, the capillary portion 41B has a large diameter, and the capillary portion 42B has a small diameter, and are connected in this order. However, the capillary portion may be formed in two stages, or may be formed in three or more stages. In addition to sequentially connecting the inner diameters from the large diameter to the small diameter, the inner diameters may be connected in any arbitrary order. However, if the number of nozzles is too small, not only will it not be possible to measure over the required range ↑, but even if you try to widen the supply amount variable range of quantitative supply means 3 to be able to measure over the required range ↑. It is not practical because the supply amount is unstable.

Therefore, the number of measurement sections and capillary sections should be determined appropriately. Further, the reason why the nozzle diameter is successively reduced in this embodiment is to improve the continuity of the flow of the viscous material.

The other measuring units 4b and 4C also have a configuration similar to that of the above-mentioned measuring unit 4a, and detailed description thereof will be omitted.

The measurement operation in this embodiment will be explained below. If the number of rotations of the fixed quantity supply means 30 is made variable, and the fixed quantity supply value of the fixed quantity supply means 3 is made variable, then Q in the above equations (1) and (2) becomes variable, and the values ↑ to η are continuously measured. sell.

In order to measure the value of η for ↑ at one measuring section, the number of capillary sections at one measuring section can be changed from one to the other by changing the number of measuring sections at multiple locations. It is possible to measure the value of η for ↑.

The effects of other configurations will be explained below. For example, pellets of thermoplastic synthetic resin are supplied from the hopper 2b. Then, the resin is heated in the casing 2a by the heater 2e, and the resin is melted by this heat and the heat generated by mechanical shearing, and is fed by the screw 2G, and the resin is fed to the supply path 2.
d. During this time, the output signals of the thermometers 14 and 15 are inputted to the control means 10, and the control means 1o controls the heaters 2e and 2'' so that these values become the pre-input values. Depending on the signal, the control means 1o controls the rotational speed of the motor 60.

The feeding amount of the metering supply means 3 is controlled by the control means 10 controlling the rotation speed of the motor 80 based on a signal from the tachometer 88.

10 is a control means to which a display device 10a is attached. The contents of the control means 10 are known computer devices, each heater 2e, 2'' and 4e, each pressure gauge 11, 12 and 13, each thermometer 14, 15, 16 and 17, the motor 6 and 8 and a tachometer 88. During this period, signals should be exchanged (connected).

In the measuring section 4, the heater 4e is controlled by the control means 10 based on the output signal of the thermometer 17 in this part, so that the temperature in this part is kept constant.

Further, the control means 10 inputs the outputs of the pressure gauges 12 and 13, calculates and outputs the sum η of the two capillary portions using the equations (1) and (2), and displays the display device 1°. Display on a. Further, the control means 10 continuously changes the motor 80 rotation speed, that is, the supply amount of the quantitative supply means 3 according to the input program, and changes the above-mentioned ↑ and η in this supply amount, that is, the above-mentioned (1), (2)
) is calculated and output continuously. In this way, the ↑ to η curve of a certain viscous material can be displayed on the display device tOa.

In the above embodiment, the switching valves 4g, 4h, 4j and each measuring section 4a, 4b, 4c are interposed, but the switching valves 1
It is also possible to use individual items.

Next, an embodiment of the second invention will be described with reference to FIG. 2, mainly focusing on differences from the embodiment of the first invention.

In this embodiment, each quantitative supply means 3a, 3b, -
The m- suction port 31 is connected in parallel to the supply path 2d, and each discharge port 32 is connected to the first pressure gauge connection chamber 43G via each switching valve 4g. In this example,
A switching valve 4g is provided for each discharge port 32, but these can be combined into one switching valve 4g to switch and connect each discharge port 32 and the first pressure gauge connection chamber 43e. You can do it like this. Furthermore, the switching valve 4g may be connected to the suction port 31 of the quantitative supply means 3a, 3b instead of the discharge port 32.

In this embodiment, the switching valve 4g is switched, and the discharge port 32 of the quantitative supply means 3a, 3b, 3C is connected to the measuring section 4, and a capillary part 41a with an inner diameter of dl and a capillary part 42a with an inner diameter of d2 are connected. By pumping viscous materials into
In the same way as above, measure the values of ↑ to η in a certain range. It is possible to measure values of ↑ to η in a wide range by sequentially switching the quantitative supply means 3a, 3b, and 3c to change the supply amount over a wide range.

The viscometer 1 of the present invention is not limited to the above embodiments (
For example, a plurality of quantitative supply means and a plurality of measurement sections may be provided, and these may be selectively switched by a switching valve.

(Effects of the Invention) As described above, the viscometer of the present invention has a plurality of measuring units arranged in parallel or a plurality of quantitative supply means arranged in parallel and connected via a switching valve, so that measurement work can be automated. This makes it easier to use, which is particularly problematic due to the configuration of the measurement range switching mechanism.
Further, there is an advantage that the extrusion pressure of the quantitative supply means does not become too large.

[Brief explanation of the drawing]

FIG. 1 is a schematic longitudinal sectional side view showing an embodiment of the first invention, and FIG. 2 is a schematic longitudinal sectional side view showing an embodiment of the second invention.

Claims (3)

[Claims] (1) It is equipped with a viscous material supply means, a quantitative supply means connected to the viscous material supply means, and a plurality of measuring parts connected to the quantitative supply means, and each of these measuring parts has a different inner diameter. The capillary section is connected in parallel to the quantitative supply means via a switching valve, and the quantitative supply means is selectively connected to any one of the measurement sections by switching the switching valve. A viscometer characterized by: (2) It comprises a viscous substance supply means, a plurality of fixed quantity supply means connected to the viscous substance supply means, and a measuring section further connected to these fixed quantity supply means, and the fixed quantity supply means measures the supply amount. and are connected in parallel via a switching valve, and the measuring section includes a capillary section, and by switching the switching valve, one of the quantitative supply means is connected to the measuring section. Features: Viscometer. (3) The viscous material supply means, quantitative supply means, measuring section, and switching valve are controlled by a control means, and the characteristic values of the viscous material can be continuously determined by the control means. The viscometer according to claims 1 and 2.