WO2001091148A1

WO2001091148A1 - Switch

Info

Publication number: WO2001091148A1
Application number: PCT/JP2000/003318
Authority: WO
Inventors: Hiroshi Funaki; Shunichi Katsube; Kazunori Fukuya
Original assignee: Mitsubishi Denki Kabushiki Kaisha
Priority date: 2000-05-24
Filing date: 2000-05-24
Publication date: 2001-11-29
Also published as: EP1199734A4; EP1199734B1; ES2233376T3; DE60017408T2; EP1199734A1; DE60017408D1; CN1358319A; KR100466789B1; JP4463470B2; KR20020021162A

Abstract

A switch, characterized as having a formed article comprising a flame-retardant material comprising 35 to 50 wt % of a resin, 20 to 60 wt % of a reinforcing material, 5 to 40 wt % of an inorganic compound which undergoes a dehydration reaction at a temperature higher than a predetermined temperature, and 0.3 to 1.8 wt % of a red phosphorus flame retardant. The switch is advantageous in that it is excellent in flame retardancy and also excellent with respect to the resistance of metal parts thereof to contamination and corrosion.

Description

Description Switch Technical Field

The present invention relates to a switch using a molded article made of a flame-retardant material having flame retardancy. Height

Conventionally, for example, Japanese Patent Application Laid-Open No. 8-171847 describes a material containing polyamide, glass fiber, and magnesium hydroxide as a flame-retardant material for a switch. .

Japanese Utility Model Application Laid-Open No. 2-1259394 discloses that flame-retardant materials for lighting fixture sockets include polyester, glass fiber, calcium carbonate, aluminum hydroxide, halogen-based flame retardants, and acid flame retardants. An article containing dani antimony is described.

Also, EP-A 1-27 855 5 contains a polyamide composition containing, for example, at least 40% by weight of a polyamide, 5 to 50% by weight of glass fiber, and 50% by weight or less of magnesium hydroxide. It contains 4 to 15% by weight of red phosphorus. The flame-retardant material for a switch described in Japanese Patent Application Laid-Open No. 7-181747 contains magnesium hydroxide as a flame retardant and imparts high flame retardancy. It is difficult to improve the flame retardancy. Further, in order to satisfy a higher flame retardancy, for example, the same flame retardancy as that containing the above-mentioned halogen-based flame retardant or red phosphorus, it is necessary to contain a large amount of magnesium hydroxide. However, when a large amount of magnesium hydroxide is contained, there is a problem in that the appearance of the molded product becomes white, and there is a problem that the pressure resistance is reduced, and it is unsuitable as a flame-retardant material for a switch.

The technology described in Japanese Utility Model Application Laid-Open No. 2-1259594 and EP-A 1-27 855 5 is not intended for switches and not only has a different technical field from the present invention. However, as will be described later, these techniques have the problem of contamination or corrosion of metal contact parts. It cannot be solved and cannot be used for switches.

The flame-retardant material of the socket for lighting equipment disclosed in Japanese Utility Model Application Laid-Open No. 2-1259394 has high flame retardancy, but is not suitable for switches for the following reasons. The reason is that this material contains a halogen-based flame retardant, and depending on the type of halogen-based flame retardant used, when used as a material for switchgear, metal parts such as contacts and electronic parts are used. This is because a problem of contamination or corrosion may occur. It is presumed that the contamination or corrosion of the metal parts is caused by the halogen gas generated from the halogen-based flame retardant over time, that is, the contamination imparting gas or the corrosion imparting gas contaminating or corroding the metal parts. In addition, halogen-based flame retardants have the potential to generate dioxins, and have environmental problems. In addition, antimony used as a flame retardant aid is a heavy metal, and may contaminate the environment.

The flame retardant material of EP-A 1-2 7 855 5 5 contains polyamide at least 40% by weight, glass fiber 5 to 50% by weight, magnesium hydroxide 50 or less, and red phosphorus 4 to 15% by weight. % And has high flame retardancy, but is not suitable for switches for the following reasons. The reason is that this flame-retardant material contains magnesium hydroxide and red phosphorus as flame retardants. According to the investigation by the present inventors, this flame-retardant material has excellent flame retardancy, It was found that there was a problem of contaminating or corroding the parts. This contamination or corrosion problem is presumed to be due to the contamination or corrosion imparting gas resulting from red phosphorus over time contaminating or corroding metal parts.

Here, contamination or corrosion means that an insulator is formed on the surface of the metal part, the contact resistance of the metal part is increased, or a highly reactive element (halogen element, phosphorus) is detected on the metal surface. At least one of the above.

The term “contamination-imparting gas or corrosion-imparting gas” refers to a gas presumed to cause contamination or corrosion.

In order to reduce the size and increase the breaking capacity of the switch, the above-mentioned decrease in insulation resistance due to the contamination or corrosion of the metal component is a major obstacle. In addition, in order to reduce the weight of switches, flame retardancy with a small thickness is required.

An object of the present invention has been made to solve the above-mentioned problem, and has an excellent flame-retardant property. It is an object of the present invention to obtain a switch having a molded product. Disclosure of the invention

In the present invention, 35 to 50% by weight of a resin, 20 to 60% by weight of a reinforcing material, 5 to 40% by weight of an inorganic compound which undergoes a dehydration reaction at a predetermined temperature or higher, and 0% by weight of a red phosphorus flame retardant. It is intended to provide a switch characterized by having a molded article made of a flame-retardant material containing 3 to 1.8% by weight.

The present invention also provides the above-mentioned switch, wherein the red phosphorus flame retardant is 0.5 to 0.8% by weight.

Further, the present invention provides the above-mentioned switch, wherein the inorganic compound is 30 to 40% by weight and the red phosphorus flame retardant is 0.5 to 1.0% by weight.

The present invention also provides the above-mentioned switch, wherein the resin is a thermoplastic resin.

The present invention also provides the above-mentioned switch, wherein the thermoplastic resin is a polyamide.

Further, the present invention provides the above-mentioned switch characterized in that at least one part of the base of the housing is provided with a molded product.

The present invention also provides the above-described switch, wherein a molded product is provided near an arc generated between the contacts, and a structural material having mechanical strength superior to the molded product is provided in other portions. To provide.

In addition, in this specification, weight% is not a so-called weight percentage but a ratio to the weight of the entire composition. That is, the sum of the above components by weight is not always 100% by weight. Detailed description of the invention

Hereinafter, the present invention will be described in more detail.

The molded article used in the present invention may contain 35 to 50% by weight of one or more kinds of thermoplastic resin, 20 to 60% by weight of reinforcing material, and a molding temperature of one or more kinds of thermoplastic resin. of Temperature) A flame retardant material containing 5 to 40% by weight of an inorganic compound that undergoes a dehydration reaction at the above and 0.3 to 1.8% by weight of a red phosphorus flame retardant, preferably red phosphorus The flame retardant is 0.5 to 0.5% by weight, or the inorganic compound is 30 to 40% by weight and the red phosphorus flame retardant is 0.5 to 0.5% by weight.

[Thermoplastic resin]

As the thermoplastic resin, polybutylene terephthalate, polyethylene terephthalate, polyamide, aliphatic polyketone, polyphenylene sulfide, or any of these aromatic materials can be applied.In particular, heat resistance, pressure resistance, arc of switchgear can be applied. Polyamide is preferred in terms of insulation performance after generation.

[Reinforcement]

The reinforcing material is one or more types selected from the group consisting of glass fibers, inorganic minerals, and ceramic fibers, and is preferably used in an amount of at least 20% by weight of glass fibers.

1: Inorganic compound 3

It is presumed that the inorganic compound contained in the molded article containing the flame retardant material and undergoing a dehydration reaction contributes to the improvement of the flame retardancy of molded C3.

When this molded product is exposed to high temperatures (for example, at a temperature of more than 340 ° C), the inorganic compounds in the molded product are thermally decomposed, and the generated water vapor suppresses the heat generation and the endothermic reaction when the water vapor is generated. It is thought that it takes away the fever.

In addition, unlike halogen-based flame retardants and red phosphorus flame retardants, inorganic compounds contained in molded articles containing flame-retardant materials and dehydrating not only do not cause metal contamination or corrosion, but also According to experiments, it was estimated that red phosphorus flame retardant had the effect of preventing metal contamination or corrosion. In particular, as the material composition of molded articles excellent in both flame retardancy and metal contamination or corrosion, look at the specific compounding ratio of an inorganic compound that undergoes a dehydration reaction at a predetermined temperature or more and a red phosphorus flame retardant! I came out.

Furthermore, inorganic compounds that are contained in molded articles containing flame-retardant materials and that undergo a dehydration reaction contribute to preventing insulation deterioration after an arc is generated between the contact points of the electrodes when the switches are opened and closed. It is estimated. When the switch is opened and closed, an arc is generated between the contacts of the electrode, and the temperature usually rises to about 4000 to 600 ° C. As a result, the internal metal components of the electrodes, contacts and switch are heated, and metal vapor or molten metal droplets are generated from the metal and scattered.

In addition to the arc, these metal vapors and molten metal droplets decompose the switch casing and the organic components inside the switch, generating free carbon. At this time, an insulative gas is generated from the inorganic conjugation compound contained in the molded article, and the insulative gas is a molded article made of a flame-retardant material when the electrode of the circuit breaker is opened and closed. And free carbon generated from internal components, sublimation metal generated from contacts and internal components, and scattered molten metal droplets. it is conceivable that. For example, inorganic compounds case of magnesium hydroxide to a dehydration reaction, occurring insulating imparting gas is presumed to H ₂ 0.

When free carbon, metal vapor, and molten metal droplets are converted into insulators by the insulating gas, high pressure vapor is generated by the arc near the contacts and expands. In this case, a layer in which free carbon, metal vapor and molten metal droplets are turned into an insulator is not formed at the contact point, and does not hinder energization.

When the inorganic compound that undergoes a dehydration reaction is kneaded with a thermoplastic resin or the like, the fl-water reaction initiation temperature is preferably 250 ° C or higher to prevent the inorganic compound from undergoing a dehydration reaction during kneading.

Inorganic compounds dehydration at 250 ° C or more, calcium aluminate _{_{(Ca 3 Al 2 (OH)}} 12), zinc borate _{_{(2 ZnO, 3B0 2 0 3}} , 3. 5H 2 0), water calcium oxide (Ca ( OH) ₂ ), magnesium hydroxide (Mg (OH) ₂ ), and the like.

Here, when the thermoplastic resin is polyamide, considering the shear heat generation in addition to the set temperature at the time of kneading the thermoplastic resin, the stiffener, the inorganic sintering compound, and the red phosphorus flame retardant, it is 340 at the time of kneading or molding. Reaches around ° C. In this case, the dehydration reaction start temperature of the inorganic compound that undergoes the dehydration reaction is preferably 340 ° C. or higher so that the inorganic compound that undergoes the dehydration reaction during kneading or molding does not cause the dehydration reaction. On the other hand, in general, Since the polymer decomposition onset temperature is between 400 ° C. and 550 ° C., if the dehydration reaction onset temperature is too high, in other words, the dehydration onset temperature of the inorganic compound that undergoes the dehydration reaction will be higher than the polymer decomposition onset temperature. If the temperature is higher than the starting temperature, the flame retardant effect cannot be sufficiently exhibited, which is not desirable. Inorganic compounds that satisfy such conditions and undergo a dehydration reaction include calcium hydroxide and magnesium hydroxide.

Magnesium hydroxide is preferred because the greater the heat absorption per unit mass, the higher the flame retardancy.

Furthermore, among the inorganic compounds that undergo a dehydration reaction, calcium hydroxide, calcium aluminate, and magnesium hydroxide are preferred because they are nontoxic.

If the weight of the inorganic conjugate that dehydrates at a temperature higher than the molding temperature of the thermoplastic resin is 40% by weight or more, the bow I tension strength is reduced, the surface of the molded product is whitened, and the appearance of the switch is poor. Tend.

[Red phosphorus flame retardant]

As the red phosphorus flame retardant, red phosphorus with an average particle size of 25 to 35 m coated with phenol was used.

When the amount of the red phosphorus flame retardant exceeds 1.0% by weight, the current-carrying characteristics tend to deteriorate, and in particular, when the amount exceeds 1.8% by weight. This tendency is presumed to be due to an increase in the proportion of red phosphorus flame retardants. Phosphine (PH ₃ ) and phosphoric acid (H ₂ P 0 ₃ ) are generated as phosphorous compounds having metal contamination or corrosiveness from the red phosphorus flame retardant, and an insulating compound is formed at the switch contact, that is, the contact. Is believed to be metal contaminated or corroded. On the other hand, when the red phosphorus flame retardant is added in an amount of less than 0.5% by weight, particularly less than 0.3% by weight, the flame retardant effect tends to be insufficient.

The weight percentage of the above red phosphorus flame retardant is based on the amount of red phosphorus.

In order to prevent the deterioration of the electrical characteristics, that is, to prevent metal contamination or corrosion, the red phosphorus flame retardant preferably contains at least one of the surface coating of red phosphorus and a phosphorus compound adsorbent. It is preferable to use a contamination or corrosion inhibitor in combination. Pollution or corrosion inhibitors are substances that suppress metal contamination or corrosion by redness. When the resin is a polyamide, a substance having an alkaline property is preferable.

Here, a molded article containing a red phosphorus flame retardant, a reinforcing material, and a thermoplastic resin without containing an inorganic compound that undergoes a dehydration reaction at a predetermined temperature or higher tends to have a reduced electric resistance after an arc is generated after being exposed to an arc. was there. This is thought to be due to the carbonized layer adhering to the inside surface of the switch housing and the surface of the internal components of the switch.

Also, red flame retardants do not generate dioxins, because they are not phenolic or logenic flame retardants.

As described above, in addition to the resin and the stiffener, the inorganic compound that undergoes a dehydration reaction at a predetermined temperature or higher with the red phosphorus flame retardant is used in combination, and in particular, the mixing ratio of the red phosphorus flame retardant and the inorganic sulfide is selected. As a result, it was possible to obtain a molded article for a switch having excellent characteristics of both flame retardancy and metal contamination or corrosion.

In other words, in this mixing ratio, the addition amount of the red phosphorus flame retardant is very small, the formation amount of the charcoal layer is also reduced, and the carbonization layer is made into an insulator by the insulating imparting gas generated from the inorganic compound that undergoes a dehydration reaction. It is considered that a decrease in electrical resistance is prevented, a decrease in insulation after arc generation is suppressed, and flame retardancy can be enhanced by both the red phosphorus flame retardant and the inorganic compound that undergoes a dehydration reaction.

By containing a trace amount (0.3 to: L. 8% by weight) of a red phosphorus flame retardant and a small amount (5% to 40% by weight) of an inorganic compound capable of dehydrating at a predetermined temperature or higher, the inorganic compound The substance alone can reach a flame-retardant level that cannot be reached without adding a large amount. At this time, the inorganic compound may be used in a relatively small amount of 5% by weight or more from the viewpoints of flame retardancy and metal contamination or corrosion, and it is possible to make the molded product thin without reducing the pressure resistance. And, as the amount of the inorganic compound was increased from 5% by weight, there was a tendency that the flame retardancy was improved.

Compared to the case where only red phosphorus flame retardant is used as the flame retardant, it is necessary to maintain the same flame retardancy by using the red phosphorus flame retardant together with an inorganic compound that undergoes a dehydration reaction at a specified temperature or higher. Red phosphorus content can be reduced, and metal contamination resistance or corrosion resistance can be improved.

If an inorganic compound that dehydrates at a predetermined temperature or higher and a red flame retardant are used together, It is considered that when the reacting inorganic compound has an alkaline property such as a hydroxide, it becomes a contamination inhibitor or a corrosion inhibitor for the red phosphorus flame retardant, and has a high effect of suppressing metal contamination or corrosion. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a cross-sectional view of a switch according to a first embodiment of the present invention, cut along a side surface.

FIG. 2 is a sectional view of the switch of FIG. 1 cut along a plane.

FIG. 3 is a perspective view including a partial cross section of a pace of a casing of a switch according to Embodiment 2 of the present invention. . Example

Hereinafter, the present invention will be described with reference to examples.

Example 1

As shown in Table 1 below, the following flammability test was performed using test pieces molded from various materials having flame retardancy.

FIG. 1 is a cross-sectional view of a switch according to a first embodiment of the present invention, which is cut on a side surface. FIG. 2 is a sectional view of the switch of FIG. 1 cut along a plane.

[Combustion test 1 (960 ° C GWF I)]

This is a flammability test described in JISC 074, in which a wire heated at 960 ° C is applied to a sample for 30 seconds, and the condition after removing the glow wire is evaluated. You.

The specimen is 75 mm square and the thickness is an arbitrary constant thickness.

The criterion is that the flame or red heat extinguish within 30 seconds and that the wrapping tissue placed under the sample does not ignite. Those who satisfy this criterion three or more times in a row are —passes at the constant plate thickness. In this evaluation, the ranking is based on the passing plate thickness.

[Fire Test 2 (HW I)]

This is the combustion test described in IEC 9471-1, in which a specified piece of wire is wound around the sample, the specified power is applied, and heating is continued until the sample is lit. After ignition, turn off the power and record the time until ignition. Perform 5 tests for each material. In this evaluation, the ignition Those with a time of 30 seconds or more are accepted.

The specimen is 150 mm long and 13 mm wide, and the thickness is arbitrary. The nikku wire is wound 5 times at intervals of 6 mm.

[Metal contamination (corrosion) test]

Using the molded product of Example 1, the following metal contamination or corrosion test was performed.

The molded article is the base 1 of the housing in FIGS. 1 and 2 '.

The contaminated object or corroded object (hereinafter referred to as the contaminated object) is a copper plate (C1101 / 4H) and a 28 x 14 xl mm plate made of silver plated copper plate. Two of these were used.

After ultrasonically cleaning the contaminated object with acetone, place the contaminated object (one copper plate and two silver plating plates) on the base bottom surface 5 shown in Fig. 2.

Then, wrap around Pace 1. This is to confine metal-contaminated gas or metal-corrosive gas generated from the base and to make it difficult for gas in the temperature chamber (environmental chamber) described later to enter the package.

Then, leave the packaged base 1 in a temperature bath (120 ° C) for 30000 hours.

After leaving in the temperature bath, the non-contact surface between the corroded body and the molded product (base 1) is analyzed by SEM (scanning electron microscope) and XMA (energy dispersive X-ray analyzer), and the metal contamination or metal corrosivity An evaluation was performed.

Here, both the contact surface and the non-contact surface with the molded article (base 1) can be considered as the measurement site of the contaminated object, but the non-contact surface should be measured and evaluated by the following preliminary study. And

After standing in the temperature bath, the contact surface between the contaminated object and the molded article (Base 1) and the non-contact surface between the contaminated object and the molded article (Base 1) are examined by SEM (scanning electron microscope) and XMA (energy). When analyzed by a monodisperse X-ray analyzer, more red phosphorus was detected on the non-contact surface between the contaminated object and the molded article (Pace 1). It is presumed that this contamination or corrosion is not the corrosion that occurs at the contact interface with the article, but rather the contamination or corrosion due to the gas ejected from the article. Therefore, as mentioned above, the metal corrosion evaluation The test was performed on the non-contact surface with the molded product (base 1).

[Contact resistance measurement]

The contact resistance was measured by leaving two pieces of silver plated from the packaged sample (base 1) after standing in a temperature bath and applying a constant contact pressure to the overlapped part. A constant current (1 A) is passed between the two plates, and the contact resistance is measured from the voltage drop at the portion where the samples are stacked.

At the time of measuring the contact resistance, the lap opening of the silver plated sample is 14x15 mm, and the contact pressure is about 98 KPa (about 1. Okg / cm ² ).

Surface analysis of the contaminated material was performed by SEM and XMA (15 KV applied to the electron gun). The analysis area of XMA is about 10x7mm square.

The surface analysis of the contaminated material is based on SEM images and XMA detection peaks (particularly, mass ratios converted from P and Ag detection peaks).

table 1

() Is estimated

One is no data

[Test results]

Next, test results will be described. Table 1 is a sample showing the test results of Samples 1 to 7.

Samples 1 to 3 are 40 to 50% by weight of nylon 6; 45 to 60% by weight of glass fiber or a mixture of glass fiber and wollastonite as a reinforcing material; and 5% by weight of magnesium hydroxide as a flame retardant. % And 1.2 to 5.4% by weight of red phosphorus. Samples 4 to 6 are 40 to 50% by weight of nylon 6, 20% by weight of glass fiber as a reinforcing material, 30 to 40% by weight of magnesium hydroxide as a flame retardant, and a very small amount of red phosphorus 0.3. It has a composition containing about 1% by weight.

Sample 7 has a composition containing 50% by weight of nylon 6, 20% by weight of glass fiber as a reinforcing material, and 30% by weight of magnesium hydroxide alone as a flame retardant.

Sample 1 (red phosphorus 5.4% by weight, magnesium hydroxide 5% by weight) shows excellent flame retardancy of 1.5 mm in the test result at 960 ° CGW FI, but has metal contamination or metal corrosion. There is a problem with sex.

When left at 120 ° C. for about 100 hours, phosphorous compounds were observed in various places on the surface by SEM and XMA, and phosphorus was detected on the silver plating surface. Also, the contact resistance of the superposed silver plating plates increased remarkably, indicating that phosphorus was detected. When a molded article made of this flame-retardant material is used as a switch case, there is a possibility that the above-mentioned compound is deposited on the surfaces of the fixed contact 2 and the movable contact 3 to cause conduction failure.

Since phosphorus was detected on the silver plating plate, analysis by SEM and XMA was not performed on the copper plate where phosphorous was more easily detected than on the silver plating plate.

Sample 2 (1.8% by weight of red phosphorus, 5% by weight of magnesium hydroxide) and Sample 3 (1.2% by weight of red phosphorus, 5% by weight of magnesium hydroxide) showed 2% in the test result of 960 ° CGWF I. It exhibited good flame retardancy of 0.2 mm, and was also good in silver plate stain or corrosion tests.

Although there was some phosphorus detection (P / Cu = 0.03) in the copper plate contamination or corrosiveness, it was a trace amount and was at a level that did not cause any problem in the use of switches. Sample 4 (red phosphorus 1.0% by weight, magnesium hydroxide 40% by weight) and sample 5 (red phosphorus 0.5% by weight, magnesium hydroxide 30% by weight) were tested at 960 ° C CGWF I. And 1.5 mm in HWI test results, indicating excellent flame retardancy. Regarding metal contamination or corrosiveness, silver plating was higher in Samples 2 and 3 which had a higher content of red phosphorus than Samples 4 and 5 and a lower proportion of magnesium hydroxide as a contamination inhibitor or corrosion inhibitor. Since no phosphorus was detected in the contamination test or corrosion test of Samples 4 and 5 where the factor of detecting phosphorus was smaller than that of Samples 2 and 3, the contamination test or corrosion test of silver plating It is presumed that no phosphorus is detected in the sample. Sample 5 is a sample obtained by adding a small amount of red phosphorus (0.5% by weight) to Sample 7, but has good metal contamination or metal corrosivity, and has a much higher flame retardancy than Sample 7. . Only magnesium hydroxide is used as a flame retardant, and in order to achieve the same flame retardancy, it is necessary to further contain a large amount of magnesium hydroxide (for example, more than 40% by weight of magnesium hydroxide). However, if magnesium hydroxide is contained in an amount exceeding 40% by weight, it is not preferable in terms of the appearance of poor appearance such as whitening of the surface of the molded article and the decrease in pressure resistance.

Sample 6 (red phosphorus 3% by weight, magnesium hydroxide 30% by weight) failed the test at 960 ° C CGWF I at 1.5 mm and passed at 2.0 mm, and the HWI test result. At 1.5 mm, it was rejected and at 2.0 mm, it passed and the flame retardancy was good. Regarding the metal contamination and the corrosiveness of the metal, no phosphorus was detected in any of the silver plating plate and the copper plate.

Sample 7 was a comparative example containing no red phosphorus, and was excellent in metal contamination or metal corrosion, but was inferior to Samples 1 to 6 in flame retardancy. From the above results, the molded articles made of the flame-retardant materials of Samples 2 to 6 have good flame retardancy and good properties of metal contamination or metal corrosivity.In addition, Sample 4 and Sample 5 It can be seen that the molded article made of the flame-retardant material is more excellent in both the characteristics of flame retardancy and metal contamination or metal corrosion.

When red phosphorus is less than 1.8% by weight and magnesium hydroxide is present in an amount of 5% or more, there is no problem in pollution or corrosion, and the effect as a pollution inhibitor or corrosion inhibitor is sufficient. Presumed. Samples 4 to 7 contain 30 to 40% by weight of magnesium hydroxide in a large amount to improve flame retardancy. Example 2

FIG. 3 is a perspective view including a partial cross section of the pace of the casing of the circuit breaker according to the second embodiment. In FIG. 3, reference numeral 11 denotes a base of a circuit breaker housing, and reference numeral 13 denotes a base having an outer surface of the base 11 and provided at a position apart from an arc generated between contacts (not shown). It is a structural material having excellent mechanical strength and is made of, for example, a thermosetting resin, a thermoplastic resin alone, or a composite of such a resin and the same reinforcing material as described in the embodiment. Reference numeral 15 denotes a base arc-receiving portion disposed at a position exposed to an arc generated between contacts (not shown) of the base 11, and is made of the composite described in the first embodiment. The paced arced part 15 is hatched for convenience of explanation. The base 11 can be obtained by arranging the composite material of the base 13 and the composite material of the paced arced part 15 at predetermined positions in a mold (not shown), and then performing heat and pressure molding of both composite materials. .

As described above, the flame-retardant molded article excellent in metal contamination or corrosion is arranged in the base arced portion 15 of the base 11, while the base 13 remote from the arc source is mechanically mounted. Made of structural material with excellent strength, it is possible to reduce the decrease in insulation resistance on the surface of the base 11 after arcing without deteriorating the creepability.

In the second embodiment, the mixture of the first embodiment is applied only to the part to be arced 15 which is a part of the inner surface of the pace 11, especially around the contact exposed to the arc and having a large decrease in insulation resistance. Although the example described above has been described, it is also effective to dispose the mixture of Example 1 on the entire inner surface of the base 11. Industrial applicability

The switch according to the present invention comprises: 35 to 50% by weight of a resin; 20 to 60% by weight of a reinforcing material; 5 to 40% by weight of an inorganic compound which undergoes a dehydration reaction at a predetermined temperature or higher; Flame retardants Has a molded product made of a flame-retardant material containing 0.3 to 1.8% by weight, so that the flame retardancy and the metal contamination or metal corrosion properties are good.

Further, when the red flame retardant is 0.5 to 1.8% by weight, the flame retardancy is further improved. Further, when the inorganic compound is 30 to 40% by weight and the red phosphorus flame retardant is 0.5 to 1.0% by weight, metal contamination or metal corrosion is further excellent.

If the resin is a thermoplastic resin, molding is easy and the thickness can be reduced.

In addition, if the thermoplastic resin is polyamide, the insulation after arcing is excellent. In addition, if the molded article is the base of the housing, it is excellent in flame retardancy, insulation after arcing, mechanical strength, and the like, and the size of the switch can be reduced.

Also, if a molded product is provided near the arc generated between the contacts and the other part is provided with a structural material having a higher mechanical strength than the molded product, the creep resistance is excellent.

Claims

The scope of the claims

1. 35 to 50% by weight of resin, 20 to 60% by weight of reinforcing material, 5 to 40% by weight of inorganic compound dehydrating at a predetermined temperature or more, and 0.3 to L.8 of red phosphorus flame retardant A switch characterized by having a molded article made of a flame-retardant material containing weight%.

2. The red flame retardant is 0.5 to 1.8% by weight.

Switch according to paragraph 1.

3. The switch according to claim 1, wherein the inorganic conjugate is 30 to 40% by weight and the red phosphorus flame retardant is 0.5 to 1.0% by weight. The resin according to claim 1, wherein the resin is a thermoplastic resin.

5. The switch according to claim 4, wherein the thermoplastic resin is polyamide.

6. The switch according to claim 1, wherein a molded product is provided on at least a part of a base of the housing.

7. The article according to claim 6, wherein a molded article is provided in the vicinity of an arc generated between the contacts, and a structural material having a higher mechanical strength than the molded article is provided in other portions. Switch.