JPH10249876A - Electric appliance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase joining force in a weld part and to prevent the generation of cracks caused by external force and thermal stress by using a thermoplastic resin composition containing glass fibers and a thermoplastic polyolefin elastomer in polyarylene sulfide in an insulating part. SOLUTION: In a part of an insulating part 5, a thermoplastic resin to which the following (I), (II), and (III) are added is used. (I) Polyarylene sulfide which mainly contains a homopolymer or a copolymer having at least a prescribed amount of a paraphenylene sulfide unit as a repeating unit and substantially linear chain molecular structure. (II) Glass fibers the average fiber diameter and number average fiber length of which are prescribed. (III) A copolymer mainly containing α-olefin, or a polymer in which at least one kind of thermoplastic polyolefin elastomer, a graft copolymer, is mixed. As a result, joining force in a weld part is increased, and the generation of cracks caused by external force and thermal stress can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric device such as a switchgear such as a circuit breaker, a transformer, a rotating machine and the like, and more particularly to a thermoplastic resin composition obtained by injection-molding an insulating portion of the electric device.

[0002]

2. Description of the Related Art FIG. 1 shows the construction of a 6 KV class switch as a switch. In the figure, 1 is a vacuum circuit breaker, 2 is a contact case, 3 is a current transformer (CT), 4 is a conductor, 5 is an insulating part, and the insulating part 5 is a metal part having a tapped hole for mounting a panel. 5a is embedded. These components are integrally molded by the insulating part 5 to form the switch 6.

In order to form the switch 6, after setting anything other than the insulating portion 5 in a mold, 60 parts by weight of glass fiber is contained in 100 parts by weight of polyphenylene sulfide resin (hereinafter simply referred to as PPS resin). Resin (PPS-1
(Referred to as resin) under the conditions shown in Table 1.

[0004]

[Table 1]

[0005]

However, this PPS
-1 resin has a drawback that the bonding strength at the weld portion is weak because it contains only glass fiber as a filler. For this reason, cracks are generated by external force or thermal stress, and the mechanical strength is reduced.

In reality, immediately after being removed from the mold, 15
As a result of spontaneously cooling the switch having a temperature of 0 ° C. to 170 ° C. to a room temperature of about 25 ° C., as shown in Table 2, cracks were generated at a ratio of 5 to 20 and no crack was generated. -20 ° C to 110 for the remaining 15 switches
Table 2 shows the results of 10 heat cycle tests at
Cracks occurred in all the switches shown in (1). Cracks occurred along the weld line formed in the portion A or B in FIG.

[0007]

[Table 2]

Therefore, an object of the present invention is to provide an electric device which solves the above-mentioned problem.

[0009]

According to a first aspect of the present invention, there is provided an electric apparatus formed by injection-molding a resin on an insulating portion of the electric apparatus. As a feature, a thermoplastic resin composition containing a glass fiber and a polyolefin-based thermoplastic elastomer in a polyarylene sulfide resin is used, and the configuration of the electric device according to claim 2, wherein the glass fiber is The fiber diameter is 3 to 15 μm and the number average fiber length is 50 to 800 μm, and the content of the glass fiber is 5 to 150 parts by weight based on 100 parts by weight of the polyarylene sulfide resin. The configuration of the electric device according to claim 3, wherein the content of the polyolefin-based thermoplastic elastomer is set to 100 weight of polyarylene sulfide resin. The composition of the electric apparatus according to claim 4, wherein the composition of the polyolefin-based thermoplastic elastomer is α
-It is characterized by comprising either one of a copolymer mainly composed of polyolefin and a graft copolymer, or a mixture of a copolymer mainly composed of α-polyolefin and a graft copolymer.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings. In this embodiment, since only the resin material of the conventional electric device is improved,
Only materials will be described.

A switch as an electric device according to the present invention, in which a portion of an insulating portion 5 shown in FIG. 1 is made of a polyarylene sulfide resin (hereinafter simply referred to as a PAS resin), made of glass fibers and a polyolefin-based thermoplastic elastomer. The added thermoplastic resin is used.

In the present invention, the PAS resin serving as a substrate is a polymer containing at least 70 mol% of a repeating unit represented by the structural formula -Ar-S- (Ar is an arylene group). It is a resin having a repeating unit represented by -Ph-S- (Ph is a phenylene group) in an amount of 70 mol% or more. Among them, a shear rate of 120 at a temperature of 310 ° C.
The melt viscosity measured under the condition of 0 / sec is 10 to 150.
Those having a poise in the range of 00 poise, especially 100 to 5000 poise are suitable. PAS resins are generally known to have a molecular structure that is substantially linear and do not have a branched or crosslinked structure, or a structure having a branched or crosslinked structure, according to the present invention. Is also effective, but a preferred PAS resin for use in the present invention is a polymer having 70 or more paraphenylene sulfide units as repeating units.
It is mainly composed of a homopolymer or copolymer having a substantially linear molecular structure containing at least mol%, more preferably at least 80 mol%. If the content of the repeating unit is less than 70 mol%, the original crystallinity, which is a characteristic of the crystalline polymer, tends to be low, and sufficient moldability and mechanical properties tend not to be obtained. Examples of the copolymerizable structural unit include a metaphenylene sulfide unit, an orthophenylene sulfide unit, a p, p′-diphenylene ketone sulfide unit, a p, p′-diphenylene sulfone sulfide unit, a p, p′-biphenylene sulfide unit, and p , P'-diphenylene ether unit, 2,6-naphthalene sulfide unit and the like. In particular, the PAS resin used in the present invention is a substantially linear high-molecular polyphenylene sulfide homopolymer in which the repeating unit is paraphenylene sulfide, and the main repeating unit is paraphenylene sulfide, and is composed of up to 20 mol% of metaphenylene sulfide. Those mainly comprising a polyphenylene sulfide copolymer are preferred. or,
As the PAS resin of the present invention, in addition to the above-mentioned substantially linear polymer, a branched or crosslinked PAS resin polymerized by using a small amount of a monomer having three or more functional groups as a part of the monomer is used. Alternatively, a polymer obtained by increasing the melt viscosity of a linear polymer having a relatively low molecular weight by oxidative crosslinking or thermal crosslinking to improve moldability may be used.

Next, the fiber diameter and the number average fiber length of the glass fibers will be described. There is no particular limitation on the glass fiber used in the present invention, and ordinary commercially available chopped glass fiber can be used, and the average fiber diameter is 3 to
15 μm glass fiber.

The number average fiber length varies depending on the manufacturing conditions of the molded product of the high-voltage equipment such as extrusion conditions and molding conditions, but is preferably 50 to 800 μm, particularly preferably 1 to 800 μm.
It is 00 to 500 μm. If the fiber length is short, the mechanical properties are inferior, and if the fiber length is long, the mechanical properties are excellent, but problems may occur in terms of moldability and the like, and in some cases, the physical properties of the weld portion are reduced. .

Further, the glass fiber is epoxy silane,
Surface treatment with aminosilane, vinylsilane, other known coupling agents and binders may be used. The content of the glass fiber is preferably from 5 to 150 parts by weight, particularly preferably from 10 to 90 parts by weight, based on 100 parts by weight of the PAS resin. In a system in which the glass fiber exceeds 150 parts by weight, the amount of glass is excessive and the moldability is inferior. ,
It is not preferable because it does not make sense of reinforcement.

The polyolefin-based thermoplastic elastomer used here is a copolymer or a graft copolymer mainly composed of an α-olefin, and includes the following copolymers and graft copolymers.

(A) Copolymer of ethylene and α-olefin having 3 or more carbon atoms (eg, propylene, 1-butene, 1-hexene, 4-methyl-1-butene, 4-methyl-1-pentene) .

(B) α-olefin (for example, ethylene,
Propylene, 1-butene, etc.) and α, β-unsaturated carboxylic acids or esters thereof (for example, acrylic acid, methacrylic acid, ethacrylic acid, maleic acid, fumaric acid or their alkyl esters, glycidyl esters, anhydrides, etc.) Copolymer.

(C) α, β is added to the copolymer (a).
A graft copolymer obtained by graft polymerization of an unsaturated carboxylic acid or a derivative thereof (for example, acrylic acid, methacrylic acid, ethacrylic acid, maleic acid, fumaric acid, or an alkyl ester, glycidyl ester, or anhydride thereof).

(D) A graft copolymer obtained by graft-polymerizing at least one of a vinyl compound such as styrene and acrylonitrile or an α, β-unsaturated carboxylic acid or a derivative thereof to the copolymer (b).

The copolymers or graft polymers (a) to (d) may be used alone or in combination of two or more, or each may be copolymerized or grafted stepwise. The polymer may be polymerized to have a multilayer structure.

These olefin-based elastomers have a higher affinity for PAS resins than other elastomers.
Interaction with glass fibers is also good. Particularly preferred materials are a graft modified product obtained by graft copolymerizing maleic anhydride or maleic imide onto a copolymer of ethylene and propylene or 1-butene, an ethylene-alkyl acrylate copolymer and maleic anhydride. A graft-modified graft copolymer, an α-olefin, particularly a copolymer of ethylene and glycidyl acrylate or glycidyl methacrylate, and at least one of styrene, acrylonitrile, alkyl acrylate, alkyl methacrylate, etc. Graft copolymers obtained by graft polymerization of at least one kind are included.

The filling amount of the polyolefin-based thermoplastic elastomer is 3 to 30 parts by weight, particularly preferably 5 to 20 parts by weight, based on 100 parts by weight of the PAS resin. If it is too small, the crack resistance is not sufficient, and if it is too large, problems arise in heat resistance and moldability, which is not preferable.

Such PPS resin, glass fiber (fiber diameter 13
Pm shown in Table 3 as a thermoplastic resin composition containing a polyolefin-based thermoplastic elastomer (ethylene glycidyl methacrylate [85/15] copolymer-polystyrene [70-30] graft copolymer).
Injection molding was performed using PS-2 to PPS-4 under the same conditions (shown in Table 1) as PPS-1 to form a switch.

[0025]

[Table 3]

[0026] 1 molded from the above PPS-2 to PPS-4
Table 4 shows the results of the heat cycle test and the heat shock test performed on the five switches. The heat cycle test was performed in a temperature range of -20 ° C to 110 ° C, and the heat shock test was performed by immersing in cold water of 5 ° C and hot water of 95 ° C.

[0027]

[Table 4]

The heat cycle test and the heat shock test of these 15 switches were performed in the following procedure.

(A) Fifteen switches were naturally cooled under the same conditions as the PPS-1 resin, and no cracks occurred.

(B) Next, a heat cycle test was performed 10 times on the 15 samples under the above conditions, and the number of cracks generated was examined.

(C) Next, a heat cycle test was further performed 10 times under the same conditions on the switch in which no crack was generated in (b) under the same conditions, and the number of cracks generated was examined.

(D) Further, a switch in which no crack was generated in (c) was subjected to a heat shock test under the above conditions, and the number of cracks was determined. Table 4 shows the results.

Next, an attempt was made to form a switch using a thermoplastic composition having a PPS-2 polyolefin-based thermoplastic elastomer content of 40 parts by weight. However, a large amount of gas was generated and the fluidity of the resin was poor. A switch could not be formed.

The number average fiber length of the glass fibers in the molded product is:
It was determined by the following method. That is, a sample cut from a molded article was ashed in an electric furnace at 600 ° C., then dispersed in ethylene glycol, and determined using an image processing apparatus.

The molded part is not limited to a switch, but may be a part used for a transformer or a rotating machine.

[0036]

As can be seen from the above description, claim 1
According to the electrical devices according to Nos. 4 to 4, since the thermoplastic resin composition containing the glass fiber and the polyolefin-based thermoplastic elastomer in the polyarylene sulfide resin was used for molding, an excellent effect that cracks are not generated as compared with the related art. To play. Therefore, an excellent electric device can be provided.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a switch as an embodiment of an electric device according to the present invention.

[Description of Signs] 6 ... Switch

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kazuo Fushimi 2-1-1-17 Osaki, Shinagawa-ku, Tokyo Inside the Meidensha Co., Ltd. (72) Shuzo Tanagaki 2-1-1-17 Osaki, Shinagawa-ku, Tokyo Stock Company Inside the company Meidensha (72) Inventor Yoshihiro Sato 2-1-1-17 Osaki, Shinagawa-ku, Tokyo, Japan Stock Company Inside the company Meidensha (72) Inventor Toru Nishizawa 2-1-1, Osaki, Shinagawa-ku, Tokyo, Japan Stock Company Inside the Meidensha ( 72) Inventor Masao Okiyokota 2-1-1, Osaki, Shinagawa-ku, Tokyo, Japan Inside the Meidensha Corporation (72) Inventor Mina Nakajima 2-1-1, Osaki, Shinagawa-ku, Tokyo Inside the Meidensha Corporation

Claims (4)

[Claims] 1. An electric device having an insulating portion formed by injection-molding a resin, wherein the resin is a thermoplastic resin composition comprising a glass fiber and a polyolefin-based thermoplastic elastomer in a polyarylene sulfide resin. Electrical equipment characterized by using objects. 2. The glass fiber having a fiber diameter of 3 to 15 μm.
2. The electric apparatus according to claim 1, wherein the number average fiber length is 50 to 800 μm, and the content of the glass fiber is 5 to 150 parts by weight based on 100 parts by weight of the polyarylene sulfide resin. 3. A polyarylene sulfide resin having a polyolefin-based thermoplastic elastomer content of
3. The method according to claim 1, wherein the amount is 3 to 30 parts by weight based on 0 parts by weight.
An electrical device according to claim 1. 4. The method of claim 1, wherein the composition of the polyolefin-based thermoplastic elastomer is grafted to one of an α-polyolefin-based copolymer and a graft copolymer, or a copolymer mainly composed of an α-polyolefin. 4. The electric device according to claim 3, wherein the electric device comprises a mixture with a copolymer.