JPS5991043A - Manufacture of resin molded item - Google Patents

Abstract

PURPOSE:To improve the mechanical strength and crack resistance of a resin molded item, by injecting a material that is inferior in fluidity that has been obtained by adding an inorganic particulate filler and glass short fiber to a thermosetting casting material into a mold by a pressure cylinder followed by hardening. CONSTITUTION:A piston 3 is moved back behind an injection port 7, and a glass reinforced casting material is injected. Previously the mold 1 has been made vacuous with a valve 9 open, and has been heated. A valve 6 provided in an injection pipe 5 is opened, and the piston 3 is moved so that the glass reinforced casting material 4 may be injected into the vacuous and heated mold 1. In this case, the piston 3 is moved forward forcibly by pressure, the hardening is carried out with the valves 6, 9 closed before the mold 1 is filled with the casting material 4, and the cast item is removed after the hardening, so that the item becomes voidless, and as a result the item is excellent in electrical resistance and mechanical property and reliability.

Description

Detailed Description of the Invention (Technical Field of the Invention) The present invention provides a 1'+
'j1vli, LL, Ii'i1 Enter into the manufacturing method of fat molded products.

[Technical background of the barrier]

Note W'-Zetsu J: 4, is the city 1ki filli tffi
Fry, Nizugure Compared to other n-sil 4 methods, it is possible to produce products with a smaller shape without voids (l), so it is widely used in solid insulation for high-voltage equipment.゛1 wide<
l;12 is used. Recently, the size of equipment has been reduced, the installation space has been reduced due to the introduction of a single company, and the total cost has been reduced.

For this reason, multi-phase integration of electrical components such as breaker switch parts and cast bushings, which had been used independently in a single phase, has been studied and partially put into practical use. Although it has become possible to reduce the size of
li': Approximately occurs. Therefore, cracks are likely to occur due to thermal stress caused by rapid heating and cooling when the equipment is in operation or stopped. In addition, for switch parts for circuit breakers, it is also necessary to take into account the shock force generated during opening and closing, and the shock electromagnetic force generated during short circuits.In particular, if cracks occur, the interphase distance may be shortened, etc. This can lead to serious accidents.Therefore, the diaphragm itself must be more resistant to cracking than ever before, and must also be of high strength.

[Problems with background technology]

Until now, epoxy resin has been used most often for the casting boxes and rims of high-voltage electric appliances, and 50% of the filling materials have been silica powder, alumina powder, calcium carbonate, and inorganic powder. It will be added later. Furthermore, a lubricating agent and a diluent 4z may be included as necessary.

Up until now, the casting work involved pouring the above-mentioned compound into a mold,
Since the product is taken out after curing, the casting material t1 needs to have a viscosity and fluidity that allows it to be poured into a mold. For this reason, inorganic particle-type filling materials have been widely used. However, if only particle-type filling is used, the cured product has a high elastic modulus and tends to be brittle, and cracks may occur due to the difference in thermal expansion coefficient with the embedded material. Moreover, the biggest drawback of cast products is that they are weak against impact forces due to the above-mentioned optical fibers, which is a major hindrance to miniaturizing electric shock absorbers and increasing the voltage. As shown in the figure, there is a limit to the strength of the cured product if only the particle-shaped filling hole is used. As a countermeasure against this, it is desirable to reinforce the cast insulating material with fibers, such as glass fibers. However, in this case, significant thixotropy is exhibited and the fluidity of the material is impaired. For this reason, it is difficult to pour into the mold using the conventional casting method. I force myself.

In addition, other methods of reinforcing fibers for electrical components include:
For example, in the case of coils for rotating machine parts, a fiber layer is formed in advance by wrapping glass tape of a desired thickness around the part itself or filling the gap with glass wool, and then the camellia fat is added to the coil. There is something tidal. Alternatively, there is a method such as filament winding, in which the fibers themselves are soaked in resin and wound around a mold to obtain a fiber reinforced layer. However, these methods cannot be used to obtain complex shapes that take into account the thickness of the resin layer, the embedding of fixing metal fittings, and the rigidity of the surface. Difficult to apply. Further, as another type of fiber reinforced phase, there is a molded phase such as BMC and SMC. Molded products according to the same month are the same as cast products! It is widely used in how to use tf4. However, in this case as well, since the manufacturing method produces a voidless product, it is not suitable for application to a high-voltage hair transfer device.

[Purpose of the invention]

The purpose of the present invention is to add short glass fibers in addition to inorganic particle fiber to a casting material mainly made of thermosetting resin such as polyester resin or epoxy plum fat, and pressurize the material with poor fluidity. By injecting into the mold with a cylinder and curing it, a cast product with superior machine strength and crack resistance than ever before can be produced.
J and IJ manufacturing methods are provided.

[Ki f'X Ming's cover]

Kienori [1] In addition to inorganic particle-type optical fibers, glass Ul
A thixotropic casting pot containing a high proportion of i #If is injected into a mold using a pressurized cylinder.

[Embodiments of the invention]

Hereinafter, with reference to an embodiment shown in Figure ζ of this book A1;
F Fr1ll is also explained.

(+) ? l’ type profit material combination The composition of the cast feed fed to the first day of the month is shown below.

;l l? 41 Lipid phase material: Bisphenol epoxy resin: 10 (1 part) Curing: 111: Modified acid anhydride: 100 parts C Filler: Silica powder: 280 parts (1 reinforced (4.・
・Glass paper agent ((length: approx. 5 V + m)...30 parts To mix the casting material, prepare two kneaders, put the resin material in one half, and filler material and reinforcing material in 1/2 volume each. 2 each I
1 volume and mix in vacuo. On the other side, measure out the hardening agent, and then measure out the remaining filling material and hardening agent and mix them in a vacuum as well. The mixing time was about 1.5 hours.

The base compound and curing agent compound mixed on the IJJ machine at the specified time are transferred to either side, and further mixed for 5 minutes in a vacuum to obtain an injection material.

(2) Casting 44 Old mold injection FIG. 1 shows a sectional view of the casting device used in the present invention. Using FIG. 1, we will explain in detail the process of pouring into the mold of Souwa.

In FIG. 1, reference numeral 1 denotes a mold for casting, which has a casting chamber 11 formed therein for obtaining a cast product, and an injection port 12 that leads from the casting chamber 11 to the outside. Exhaust port 1
3 will be provided. The injection port is connected to a pressurized injection cylinder 2 through an injection pipe 5 having a pulp 6 in the middle. Further, the exhaust port 13 is connected to a vacuum suction device (not shown) through an exhaust pipe 8 having a pulp 9 in its intermediate portion. front 6
The cylinder 2 is provided with a 17iHf oil injection lower on its periphery 11, and a piston 3 is provided inside thereof so as to be movable forward and backward.

The piston 30 is driven by a hydraulic system (not shown), etc.
The resin injection lower J in the cylinder 2 moves forward and backward in the range from the rear position (right side in the figure) until it comes into contact with the inner bottom (left side in the figure).

Next, the process of performing casting using this casting dazzle will be explained in detail.

move the piston 3 rearward from the resin injection lower,
Note the glass-reinforced casting month explained in (]) M above. Also, in the mold 1, open the valve 9 beforehand. Drain and heat. And] Input pipe 5
Turn the valve 6 installed on the
The mold 1 is moved to the left to be evacuated, heated, and a glass reinforced molding phase 4 is injected into the mold 1. This:1. ! 9th gear, piston 3 weighs approximately 100 kg
Forcibly extrude with a pressure of 1 cr/1. When the mold 1 is filled with the glass reinforced mold 4, the bulb 6
．． 9 is closed to perform curing, and after curing, the mold is released. Repeat the same procedure below.

By using such a casting device, it is possible to cast even gravestones that are extremely thixotropic. Moreover, since the casting phase material is oily when poured, the reinforcing fibers are uniformly dispersed and no directionality is observed. Furthermore, the mechanical properties and thermal shock resistance showed values that were 1.5 times or more higher than those of the previous products.

In order to verify the above properties, a bending test, a Charpy impact test, and a crack resistance test were conducted, and the properties were compared with conventional casting materials. The details of the test method are shown below.
The results are shown in the table below.

(1) Bending test method The tip of the insulator 22 for a 6000 V circuit manufactured using the casting device shown in Fig. 1 was fixed to the identification jig 21 with bolts 23 as shown in Fig. 2. Attach the jig 20 integrally to the load receiver at the other end, and join the jig 20 with 1:! A load P was applied to the tall position from the dimension a (for example, 50 mm), and the breaking load was determined. As a result, as shown in the table above, the weight of the cast product according to the present invention was 1450 I (g), which was a significant improvement compared to the conventional product's weight of 920 kg.

(2) Charpy impact test method J1. Compliant with SK 6911. As a result, as shown in the table above, it improved to 05 compared to 43 for the conventional product.

(3) Method of crack resistance test The stiffness and rack test sample shown in FIG. 3 was used as the sample. An epoxy cast sample 24 with a thickness of 16 m/m and a diameter of 50 m/in was used, and a molded sample 24 with a thickness of 8.5 m/in was placed inside it.
'm, outer diameter 40 m/m, inner diameter 20 m/m mild steel plate M 20 flat washer 25, width 10 m/rn diameter 3
A number of phases were manufactured in which 26 pieces of kraft paper rolled at 0 m/in were charged. The crack resistance is determined by repeatedly exposing the product to the high temperature side for 30 minutes while it is open, and (for the +-temperature side, exposing it to the dry ice-alcohol bath for 10 minutes each.
Each temperature difference was made to increase as the number of repetitions increased. In addition, the rigid crack index was calculated by calculating the product of the number of cycles in which cracks occurred and the number of samples in which cracks occurred for each sample, and dividing the sum by the total number of samples. As a result, as shown in the table above, compared to 65 for the conventional product, the product according to the present invention showed a significant improvement of 18.6.

〔Effect of the invention〕

As described above, according to the present invention, the mechanical properties of the fibrous material are improved, and the poor fluidity of the casting phase caused by condensation can be solved by pressurized injection using a piston. I decided to make a voidless product because it is possible to cast it. In addition, a highly reliable cast product with excellent electrical insulation properties and A1 mechanical properties can be obtained.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view showing an example of a coffin-forming device for carrying out the method of the present invention, Fig. 2 is a side view showing a bending test state for a 6000 V circuit insulator, and PyA figures (a) and (b) are FIG. 2 is an XV side view and a front view showing the shape of a rack test sample. DESCRIPTION OF SYMBOLS 1... Mold, 2... Cylinder, 3... Piston, 4... Molding material, 5... Resin injection piping, 6... Valve, 7... Resin injection port, 8 ...Exhaust pipe, 9...
Valve, 20・Load receiving jig, 21・Fixing jig, 22・
...6000 V circuit insulator, 23... Volt, 24
...Casting 1 material, 25...M20 flat washer, 26
...Kraft paper, (7317) Agent: Kensuke Chika, patent attorney (
(1 person per page) Figure 3

Claims (1)

[Claims] Me, 1~cured 1/Ig l+'i: 5~50% glass fiber with a length of 501cm or less, depending on the cast insulation material mainly made of l fat.
A method for manufacturing a resin molded product, which includes containing 1 part of heavy M and placing the main mouth 1 into the mold using a pressurized cylinder.