JP2004162548A - Gear pump and spinning method using the same - Google Patents

Abstract

When a fluid containing particles is supplied, the particles enter between a movable part and a non-movable part inside a gear pump and bite, thereby preventing abnormalities due to poor discharge and damage to parts, and stabilizing for a long time. The present invention provides a gear pump capable of feeding liquid and a method for feeding a spinning stock solution containing particles and discharging the spinning stock solution from a spinneret stably for a long time using the gear pump.
A gear pump having a minimum side clearance of 10 to 40 μm, a minimum top clearance of 20 to 60 μm, and a minimum metal clearance of 15 to 90 μm, and feeds a spinning solution containing particles having a maximum particle size of 10 to 20 μm by the gear pump. There is a spinning method in which a liquid is discharged from a spinneret.
[Selection diagram] None

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a gear pump for feeding a fluid containing particles and a spinning method using the gear pump to feed a spinning solution composed of a fluid containing particles and discharge the solution from a spinneret.
[0002]
[Prior art]
Conventionally, various gear pumps have been proposed as gear pumps for sending a fluid such as a molten resin. For example, Patent Literature 1 proposes a method of suppressing the occurrence of metal wear occurring on a metal sliding surface in a gear pump, and preventing a decrease in pump efficiency.
[0003]
However, in this technique, when a fluid containing particles is sent for the purpose of imparting functionality or the like, the particles intrude between the movable part and the non-movable part inside the gear pump, the bite occurs, and an abnormality due to a discharge failure or the like occurs. It was difficult to prevent damage to parts.
[0004]
In particular, when feeding a spinning solution containing particles having a large particle size for the purpose of imparting functionality, there has been a problem that abnormalities due to poor discharge and damage to parts occur in a short time.
[0005]
[Patent Document 1] Japanese Patent Application Laid-Open No. 11-13644
[Problems to be solved by the invention]
The present invention is to solve such a problem in the prior art.When a fluid containing particles is sent, the particles enter between a movable part and a non-movable part inside the gear pump, and biting occurs. , A gear pump that can prevent abnormalities due to poor discharge and damage to parts, and that can supply liquid stably for a long time, and a spinning method that uses this gear pump to stably supply a spinning solution containing particles and discharge it from a spinneret. It provides a method.
[0007]
[Means for Solving the Problems]
A first gist of the present invention resides in a gear pump having a minimum side clearance of 10 to 40 μm, a minimum top clearance of 20 to 60 μm, and a minimum metal clearance of 15 to 90 μm.
[0008]
A second gist of the present invention is a gear pump having a minimum side clearance of 10 to 40 μm, a minimum top clearance of 20 to 60 μm, and a minimum metal clearance of 15 to 90 μm, and a spinning solution containing particles having a maximum particle size of 10 to 20 μm. This is a spinning method in which liquid is sent and discharged from a spinneret.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be specifically described.
[0010]
FIG. 1 is an example of a gear pump according to the present invention.
[0011]
The gear pump comprises a plate 1, a gear case 2, a gear 3, and a gear shaft 4. The clearance between the movable parts and the non-movable parts inside is the top clearance (D1-D2) between the top of the gear and the gear case, and the clearance between the plate and the gear. There is a side clearance (t1-t2) and a metal clearance (d1-d2) between the gear shaft and the gear bearing (plate).
[0012]
The minimum value of each clearance was defined as the minimum clearance.
[0013]
In the present invention, it is necessary that the minimum side clearance is 10 to 40 μm, the minimum top clearance is 20 to 60 μm, and the minimum metal clearance is 15 to 90 μm.
[0014]
If the minimum side clearance is less than 10 μm, the minimum top clearance is less than 20 μm, and the minimum metal clearance is less than 15 μm, particles enter between the movable and non-movable parts inside the gear pump when feeding fluid containing particles, and bite. If the minimum side clearance exceeds 40 μm, the minimum top clearance exceeds 60 μm, and the minimum metal clearance exceeds 90 μm, the discharge efficiency of the gear pump decreases and the discharge unevenness occurs. Cause.
[0015]
In the present invention, the discharge efficiency is preferably 98% or more when the gear pump capacity is 0.6 to 3.4 cc / rev.
[0016]
If the above conditions are not satisfied, the discharge efficiency of the gear pump is reduced, and thus the discharge is likely to be uneven.
[0017]
The discharge efficiency is calculated as follows.
[0018]
Using a test solution having a viscosity of 10 Poise, the discharge amount discharged at a rotation speed of 20 rpm, an ambient temperature of 20 ° C., a suction side pressure of 0.1 MPa, and a discharge side pressure of 0.1 MPa is a discharge amount A, and under the same conditions, a suction side pressure of 0.1 MPa. The discharge amount discharged at a discharge side pressure of 6.0 MPa is defined as a discharge amount B, and the discharge amount B / the discharge amount A is defined as a discharge efficiency.
[0019]
Furthermore, according to the spinning method using a gear pump having a minimum side clearance of 10 to 40 μm, a minimum top clearance of 20 to 60 μm, and a minimum metal clearance of 15 to 90 μm according to the present invention, large particles having a maximum particle size of 10 to 20 μm are obtained. Even if the spinning solution composed of the fluid is sent for a long time, it is possible to prevent the occurrence of abnormalities due to poor discharge of the gear pump, breakage of parts, etc., and to achieve stable spinning.
[0020]
Examples of the particles having a maximum particle size of 10 to 20 μm include inorganic particles such as silica, alumina, calcium carbonate, talc, titanium oxide, and strontium aluminate. The maximum particle size was measured using a particle size distribution analyzer LMS24 manufactured by Seishin Enterprise Co., Ltd.
[0021]
The spinning solution is a molten polymer of a thermoplastic resin such as polyethylene terephthalate, polypropylene, and nylon. Examples thereof include those in which a resin such as acetate or acrylic is dissolved in a solvent.
[0022]
【Example】
Hereinafter, the present invention will be described with reference to examples.
[0023]
The gear pump breakage rate indicates the ratio of the gear pump broken in less than three days to the number of gear pumps used, in which 16 gears were spun using eight gear pumps.
[0024]
(Example 1)
A masterbatch (hereinafter abbreviated as MB) is produced by melt-shaping 60% by weight of a polyethylene terephthalate resin and 40% by weight of a luminous pigment "Pikarico SAD-5A" (manufactured by Chemitech Co., Ltd.) having a maximum particle size of 10 μm. did. This MB was arranged in a core component, and a polyethylene terephthalate resin was used as a sheath component. The core-sheath ratio (volume ratio) was 1 / 1.6, the minimum side clearance was 30 μm, the minimum top clearance was 28 μm, and the minimum metal clearance was 34 μm. Using a rev × 2 gear pump (discharge efficiency: 99, 2%), melted at a temperature of 285 ° C., melt-spun with a 0.30 mm × 24 hole composite spinning nozzle having a round cross section, and a take-up speed of 1,400 m / min. After winding, an undrawn yarn to which a luminous pigment was added was obtained.
[0025]
No gear pump was broken in less than three days, and spinning was possible without breakage of the gear pump for one week or more.
[0026]
(Example 2)
Luminescent properties were obtained under the same conditions as in Example 1 except that discharge was performed using a 0.6 cc / rev × double gear pump (discharge efficiency of 99.6%) having a minimum side clearance of 20 μm, a minimum top clearance of 28 μm, and a minimum metal clearance of 34 μm. The undrawn yarn to which the pigment was added was spun.
[0027]
There was no gear pump broken in less than 3 days, and stable spinning was possible.
[0028]
(Comparative Example 1)
Luminescent properties were obtained under the same conditions as in Example 1 except that discharge was performed using a 0.6 cc / rev × double gear pump (discharge efficiency of 99.9%) having a minimum side clearance of 8 μm, a minimum top clearance of 28 μm, and a minimum metal clearance of 34 μm. The undrawn yarn to which the pigment was added was spun.
[0029]
All gear pumps broke in one day.
[0030]
(Comparative Example 2)
The same procedure as in Example 1 was carried out except that the discharge was performed using a 0.6 cc / rev × double gear pump (discharge efficiency of 99.7%) having a minimum side clearance of 13 μm, a minimum top clearance of 15 μm, and a minimum metal clearance of 34 μm. An unstretched luminescent fiber was obtained. Table 1 shows the obtained spinning test results.
[0031]
(Comparative Example 3)
A luminous pigment was prepared under the same conditions as in Example 1 except that a 0.6 cc / rev × double gear pump (discharge efficiency 98.2%) having a minimum side clearance of 50 μm, a minimum top clearance of 20 μm, and a minimum metal clearance of 34 μm was used. The added undrawn yarn was spun.
[0032]
Since the minimum side clearance was more than 40 μm, the discharge efficiency of the gear pump was reduced, and discharge unevenness occurred, so that stable spinning could not be performed.
[0033]
【The invention's effect】
According to the present invention, when a fluid containing particles is sent, the particles enter between the movable part and the non-movable part inside the gear pump and bite, thereby preventing abnormalities due to poor discharge, damage to parts, and the like, and A gear pump capable of supplying liquid stably and a gear spinning solution containing particles can be supplied and discharged from the spinneret stably for a long time using the gear pump.
[Brief description of the drawings]
FIG. 1 is an example of a gear pump of the present invention. FIG. 2 is an example of a gear pump of the present invention.
1: Plate 2: Gear case 3: Gear 4: Gear shaft

Claims (3)

A gear pump having a minimum side clearance of 10 to 40 μm, a minimum top clearance of 20 to 60 μm, and a minimum metal clearance of 15 to 90 μm. 2. The gear pump according to claim 1, wherein the discharge efficiency is 98% or more when the gear pump capacity is 0.6 to 3.4 cc / rev. A gear pump with a minimum side clearance of 10 to 40 μm, a minimum top clearance of 20 to 60 μm, and a minimum metal clearance of 15 to 90 μm. Method.

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