JPH01292233A - Viscometer - Google Patents

Abstract

PURPOSE:To successively supply a viscous substance to be tested and to also change the amount thereof, by constituting a viscometer of a viscous substance supply means, a quantitative supply means, nozzles having different diameters and a measuring part arranged in series sequentially. CONSTITUTION:A viscous substance as a sample is sent to a quantitative supply means 3 by a supply means 2 and accurately determined by the quantitative supply means 3 to be continuously sent out and supplied to the nozzles 4a, 4b having different diameters of a measuring part 4. At this time, when a quantitative feed amount is set to Q, the diameter of the nozzle is set to (d), the pressure difference between the inlet and outlet of the nozzle is set to DELTAP and the length of the nozzle is set to L, the relational expressions of gamma=f(Q, d) and eta=f(Q, DELTAP, L/d) are formed, and gamma and eta are calculated from said expressions. Further, when the diameters of the nozzles 4a, 4b are changed, the measured values corresponding to the number of the nozzles 4a, 4b are calculated and, if the quantitative feed amount Q is changed, measurement can be performed over a further wide range.

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 viscosity of a viscous material is an important factor. That is, the state of the flow of the molten synthetic resin, for example in the mold, is influenced by the above-mentioned t~η characteristics, and it is necessary to know the p~ and η characteristics of the synthetic resin used when designing the 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, solid synthetic resin in the form of pellets or powder is placed in a dosing tank and heated to melt, and then a piston is used to extrude the molten synthetic resin from the capillary for measurement. In addition, in the double cylinder method, a solid synthetic resin is placed inside the outer cylinder, heated and melted, and then the inner cylinder is immersed in the outer cylinder, and the outer cylinder is rotated. It is used to measure.

On the other hand, in order to maintain sufficient data on t~η for many types of synthetic resins, it is necessary to be able to measure easily not only in laboratories but also in factories. Although it would be desirable to have a small, inexpensive viscometer that can operate completely automatically, from this point of view, the above-mentioned viscometer has the following drawbacks.

+11 These viscometers use a batch method in which a fixed amount of solid synthetic resin is loaded into the measurement section, heated and melted, and then measured. If there is more than a certain amount of time until the next measurement (
(for example, for more than one day), and requires the troublesome work of disassembling and cleaning the measuring section.

In the double cylinder method, there is a method in which the outer cylinder used to load the sample is 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. not present.

In particular, when filling the sample using 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 skill.

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

(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 not fully automated.

(2) A measurement range switching mechanism is required to measure the entire range.

(Means for Solving the Problems) A viscometer 1 according to the present invention will be explained with reference to FIG. 1.

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 nozzles 4a, 4b, which are connected to the quantitative supply means 3 and have different diameters.
It is of a capillary type, and is equipped with a measuring section 4 connected in series.

(Function) The viscous material is sent to the quantitative supply means 3 by the viscous material supply means 2. The fixed quantity supply means 3 continuously and accurately sends out a fixed quantity of the viscous material, and supplies it to the nozzles 4a, 4b, . . . of different diameters of the measuring section 4.

If the above-mentioned fixed amount feed is Q1, the nozzle diameter is d1, the pressure difference between nozzle input and output is ΔP1, and the nozzle length is L, then as is well known, door = f (Q, d)... ... Belly = f
(Q, ΔP, L/d) . . . From the relational expression (2), n and η can be determined.

Furthermore, the diameters of the nozzles 4a, 4b... are dl, d, .
. . . Therefore, it is not only possible to obtain measurement values corresponding to the number of nozzles 4a, 4b, .

(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. A supply path 2d is connected to the lower part of the casing 2a. On the other hand, a variable speed motor 6 for driving the viscous material supply means 2 is provided, and the output shaft of this motor 6 is connected to the input shaft of the reducer 5 by a coupling 7. 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.

Furthermore, the viscous material supply means 2 is provided with heaters 2e, 2f, . . . and thermometers 14, 15, . Further, a pressure gauge 11 is provided in the supply path 2d.

For example, a gear pump is used as the quantitative supply means 3,
Its suction port is connected to the supply path 2d, and its discharge port is connected to the measuring section 4. 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 8a. 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.

The measurement section 4 is provided with a first pressure gauge connection chamber 4C on its inlet side, and a pressure gauge 12 and a thermometer 16 are connected to the first pressure gauge connection chamber 4C.

A first nozzle 4a is connected between the first pressure gauge connection chamber 4C and the second pressure gauge connection chamber 4d, and a pressure gauge 13 and a hygrometer 17 are connected to the second pressure gauge connection chamber 4d. ing. Note that one end of the second nozzle 4b is connected to the second pressure gauge connection chamber 4d, and the other end is open to the atmosphere. Therefore, the pressure difference Δp for the first nozzle 4a is the pressure difference between the pressure gauges 12 and 13.
This is the difference in reading from the second nozzle 4b, which is the pressure difference Δ
p is the difference between the reading of the pressure gauge 13 and the atmospheric pressure.

In this embodiment, the first nozzle 4a has a large diameter, and the second nozzle 4a has a large diameter.
b has a small diameter and the nozzles are connected in this order, but the nozzle diameter may be two stages or 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. That is, in this embodiment, since the rotation speed of the constant supply means 3 is made variable and the constant supply value of the constant supply means 3 is made variable, the above +11, Q in equation (2) becomes variable, and the door to The value of η can be measured. However, if the number of nozzles is too small, it will not be possible to measure the entire required area of the inlet, so the nozzle diameter and number of nozzles 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.

In this way, pellets of thermoplastic synthetic resin, for example, 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 2C to reach the supply path 2d. During this time, thermometer 1
The output signals 4 and 15 are input to the control means 10, and the control means 10 controls the heaters 2e and 2f so that these values become the previously input values. Further, based on the output signal of the pressure gauge 11, the control means 10 controls the motor 6.
control the rotation speed of the

The feeding amount of the quantitative supply means 3 is controlled by the control means 10 controlling the rotational speed of the motor 8 based on a signal from the tachometer 8a.

10 is a control means to which a display device 10a is attached. The content of the control means 10 is a known computer device, and the control means 10 is a known computer device, and is connected to the heaters 2e, 2f and 4e1, the pressure gauges 11, 12 and 13, the thermometers 14, 15, 16 and 17, the motors 6 and 8, and the tachometer 8a. are connected to receive and receive signals.

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.

Furthermore, the control means 10 inputs the outputs of the pressure gauges 12 and 13, calculates p and η at the two locations of the first nozzle 4a and the second nozzle 4b using the above-mentioned (+l, Furthermore, the control means 10 continuously changes the rotation speed of the motor 8, that is, the supply amount of the quantitative supply means 3 according to the input program, and the above-mentioned t and η at this supply amount, that is, Q.
tl+ is calculated using equation (2) and output continuously. In this way, the p~η curve of a certain viscous substance can be displayed on the display device 10a.

(Effects of the Invention) Since the viscometer of the present invention has the above-described configuration, it exhibits the following unique effects.

ill To supply the viscous substance to be measured, the viscous substance supply means and quantitative supply means are connected, so the viscous substance can be supplied sequentially, and the amount is not constant for one measurement like in a conventional viscometer. Since any amount can be supplied, rather than the quantity, the t~η value can be continuously determined.

(2) Furthermore, since multiple nozzles with different diameters are connected in series, it is possible to obtain the same number of η values as the number of nozzles even for a constant flow rate, without switching the measurement range. Can measure over a wide range.

(3) Due to the above, no special skill is required to operate the viscometer, and measurement requires almost no effort.

(4) Can be made small and inexpensive.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view showing an embodiment of the present invention. l... Viscometer, 2... Viscous substance supply means, 2e12f
...Heater, 3...Quantitative supply means, 4...Measuring section, 4a...First nozzle, 4b...Second nozzle, 4
e... Heater, 10... Control means.

Claims (4)

[Claims] (1) Comprising a viscous material supply means, a quantitative supply means connected to the viscous material supply means, and a measuring section connected to the quantitative supply means and in which a plurality of nozzles of different diameters are connected in series. A capillary type viscometer that is characterized by: (2) The viscometer according to claim 1, wherein the constant supply means has a variable constant supply value. (3) The viscometer according to Claims 1 and 2, wherein the plurality of nozzles having different diameters are arranged in series so that their inner diameters become successively smaller. (4) The viscous material supply means, quantitative supply means, and measuring section are controlled by a control means, and the characteristic value of the viscous material can be continuously determined by the control means, Patent A viscometer according to claims 1, 2 and 3.