WO2002017343A1

WO2002017343A1 - Circuit breaker

Info

Publication number: WO2002017343A1
Application number: PCT/JP2000/005526
Authority: WO
Inventors: Hitoshi Ito; Koji Hikake; Hiroyuki Kakisako; Susumu Takahashi
Original assignee: Mitsubishi Denki Kabushiki Kaisha
Priority date: 2000-08-18
Filing date: 2000-08-18
Publication date: 2002-02-28
Also published as: EP1229566A1; JP4445197B2; CN1233010C; EP1229566A4; DE60035521T2; DE60035521D1; TW464895B; CN1379911A; EP1229566B1

Abstract

A circuit breaker which is excellent in heat resistance and oxidation resistance in lubricating an open/close mechanism and provides an extended, stable operation, and which comprises an open/close mechanism (A) housed in an insulating case (1) and for opening/closing a movable contact (3) from/to a fixed contact (2), an engaging unit (B) engaging with the open/close mechanism (A), and a tripping mechanism (C) for freeing the engagement of the engaging unit (B) when an over-current is detected in a cable way and separating the movable contact (3) from the fixed contact (2), wherein a part of the open/close mechanism (A) is formed of a material containing iron or iron compound, and its sliding portion is provided with a lubricating oil formed by adding 1 to 5wt.% of molybdenum disulfide to an oxidation inhibitor-added phenyl ether oil.

Description

Description Circuit breaker Technical field

The present invention relates to a circuit breaker in which an opening / closing mechanism for opening / closing a movable contact is accommodated in an insulating case. Background art

Conventionally, for example, Japanese Patent Application Laid-Open No. H11-112888 discloses that a movable contact is brought into and out of contact by a handle operation, and a trip portion is provided when an overcurrent is applied. There is disclosed a circuit breaker in which an opening / closing mechanism for actuating a movable contact to separate the movable contact is accommodated in an insulating case. Most of the opening and closing mechanism portion Ri Contact formed Ri by the iron was nitrided cold-rolled steel sheet, mineral oil and effect to the F e 3 0 ₄ layer or dark-outs provided the surface at its sliding portion Lubricating oil / grease based on rib synthetic hydrocarbon oil is lubricated or applied.

However, recently, with the demand for downsizing of circuit breakers, the switching mechanism and the insulation case tend to be downsized. Also, with the demand for higher performance of circuit breakers, for example, it is necessary to house electronic components and the like for achieving new functions in an insulating case. The opening and closing mechanism tends to be smaller than before. When the size of the insulation case is reduced, the temperature inside the insulation case and the opening / closing mechanism during energization increases compared to conventional circuit breakers with the same rating, and mineral oil or aliphatic synthetic carbon is used. Lubricating oils and greases based on hydrogen oil are easily oxidized and deteriorated. In addition, when the opening / closing mechanism is downsized, its components are downsized and the space between the components is narrowed. As a result, the lubricating oil and grease are thinned, and they are easily oxidized and deteriorated. In addition, they are more likely to stick during oxidative degradation.

In addition, Japanese Patent Application Laid-Open No. Hei 7-199018 discloses a refrigeration cycle having a compressor. Then, polyphenyl ether, which is incompatible with the refrigerant for the compressor, as a lubricating oil for the compressor, and molybdenum disulfide, tantalum disulfide as its additives. It is disclosed to add tungsten, graphite fluoride, polytetrafluoroethylene, and the like. However, the compressor is not only different in technical field from the circuit breaker, but also the lubricating oil for the compressor has the characteristics required for the mechanical parts of the circuit breaker, especially at high temperatures. Since the oxidation resistance during use is different, the present invention cannot be derived.

The present invention has been made to solve the above-described problem, and has as its object to obtain a circuit breaker that is excellent in lubricating heat resistance and oxidation resistance of an opening / closing mechanism and has stable operation for a long period of time. I do.

It is another object of the present invention to provide a circuit breaker with high assembling efficiency using only lubricating oil having excellent heat resistance and oxidation resistance as a lubricant for the switching mechanism. Disclosure of the invention

A circuit breaker according to the present invention includes an insulating case, an opening / closing mechanism that is housed in the insulating case and opens and closes the movable contact, and an engaging portion that engages with the opening / closing mechanism. And a trip mechanism for releasing the engagement of the engaging portion when the current is detected and separating the movable contact from the fixed contact, wherein a part of the opening / closing mechanism is iron. Or, a circuit breaker formed of a material containing an iron compound, wherein a phenyl ether-based lubricant to which an antioxidant is added is applied to a sliding portion of the above-mentioned material containing iron or an iron compound. Since it is provided, the heat resistance and oxidation resistance of the lubrication of the opening and closing mechanism are excellent, and the operation is stable for a long time. Also, the sliding portion of the material containing iron or iron compound, the F e ₃ 0 ₄ layer or main tree key film is provided, oxidative degradation promoting action on full Wenirueteru based lubricant with a metal catalytic action of iron Is suppressed.

In addition, since the phenyl ether-based lubricant is a phenyl ether-based oil, it can be lubricated, and it is easy to impart lubricity to the sliding parts of the mechanism, which is being miniaturized.

In addition, molybdenum disulfide is added to the phenyl ether type oil, so that a thick oil film can be easily maintained and the oxidation resistance is further improved, and lubrication such as load resistance and durability is maintained. Also excellent in properties.

In addition, since molybdenum disulfide is 1.0 to 5.0 wt%, it is possible to maintain both oil film thickness excellent in oxidation resistance and dispersion stability of molybdenum disulfide.

In addition, since a phenyl ether-based oil is provided at the engaging portion between the engaging portion and the urging portion, the lubricating oxidation resistance is excellent and the operation is stable for a long time.

In addition, since the phenyl ether lubricant is a phenyl ether grease containing a urea-based increasing agent, it has excellent shape retention at high temperatures, and therefore has an acid resistance to the lubrication of the opening / closing mechanism. It has excellent lubricity and stable operation over the long term, and also has excellent lubricity. Brief description of the drawings

FIG. 1 is a perspective view of a circuit breaker according to Embodiment 1 of the present invention. FIG. 2 is a sectional view taken along the line II-II of the circuit breaker shown in FIG. FIG. 3 is a diagram showing evaluation results of the lubricating oil according to Example 1 of the present invention. FIG. 4 is a diagram showing the evaluation results of the grease according to the first embodiment of the present invention. FIG. 5 is a diagram showing the lubricating oil and the lubrication according to the second embodiment of the present invention when the grease withstands a load. It is a figure showing a characteristic. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail. Embodiment 1

FIG. 1 is a perspective view of a circuit breaker according to Embodiment 1 of the present invention, and FIG. 2 is a cross-sectional view of the circuit breaker of FIG. 1 taken along a line II-II.

In FIGS. 1 and 2, reference numeral 1 denotes an insulating case formed of an insulating resin material. The base 1a on which the stationary contact 2, the opening / closing mechanism A, etc. are installed, and a handle. It consists of a cover lb with an opening that allows 22 to protrude to the outside. 2 is a fixed contact fixed to the base la, 3 is a movable contact that is opened and closed by an opening and closing mechanism, and 4 is formed of an insulating resin material. Insulation holder through which the force is transmitted from the connecting pin 15a of the toggle link 15 that passes through the through hole. 11 is a latch 12 at one end and a trip bar 19 at the other end. The latch that engages with the lever 13 is always urged counterclockwise by the urging spring (not shown) around the coupling pin 12a, and the latch that engages with the lever 13 Is a toggle link consisting of the lower link connected to the insulation holder 4 and the upper link connected to the lower link by the lever 16 and the connecting pin 15b, and 16 is the upper link. Between the connecting pin 15b of the lower link and the knob arm 23 fixing the knob 22 And 17 are provided on the electric circuit between the flexible stranded wire 25 connected to the movable contact 3 and the external terminal 26, and are deformed by heat generated in accordance with the current flowing through the electric circuit. The metal 18 is provided on the electric circuit between the flexible stranded wire 25 connected to the movable contact 3 and the external terminal 26, and is energized when the electric current of the electric circuit exceeds a predetermined value. Electromagnetic device operated by magnetic force in response to electric current, 19 is always A bias is turned counterclockwise by the biasing panel, and when overcurrent flows through the circuit, the trip rotates clockwise due to the operation of the bimetal 17 or the electromagnetic device 18. Reference numeral 20 denotes an open / close contact provided at one end of the fixed contact 2 and the movable contact 3. The force injuries 11, the latches 12 and the levers 13 are pivotally supported on iron frame by the pins lla, 12a, 15a, 15b, and 19a. Have been.

When an overcurrent is applied, the no metal 17 or the electromagnetic device 18 rotates the trip bar 19 to release the lock between the force injuries 11 and the latches 12, and the latches. In the step 12, the lock of the lever 13 is released, and the energy stored in the main panel 16 opens and closes the switching contact 20 to cut off the current. After the tripping operation of the circuit breaker, the reset operation resets the locking of the power injuries 11, the latches 12, and the levers 13 and closes the on / off contact 20. Thus, it is configured so as to be prepared for the current interruption again.

The opening / closing mechanism A that opens and closes the movable contact 3 includes an iron plate frame, a handle arm 23, a handle 22, a reno 13, and (a toggle link 15 and a main panel 16). It consists of a toggle link mechanism. Further, an engaging portion B which engages with the opening / closing mechanism portion A by the latch is constituted by a force damper 11 and a latch 12. In addition, in accordance with the overcurrent of the electric circuit, the releasing portion C for releasing the latching portion of the engaging portion: B is connected to the bimetal 17, the electromagnetic device 18, and the trip bar 18. It is composed of

The above-mentioned frames, force injuries 11, latches 12, levers 13, toggle links 15, etc. are usually formed by pressing low-carbon steel cold-rolled steel plates (SPCC-SD). It has been subjected to nitriding (gas nitrocarburizing) for the purpose of surface hardening, strength improvement and protection.

Then, bearings with shaft pins 11a, 12a, 15a, 15b, 19a, force injuries 11, latches 12, levers 13, toggle links 1 5 The following phenyl ether-based lubricating oil is lubricated to the sliding parts of the parts in order to reduce the friction in sliding between parts and to operate smoothly.

C lubricant]

The lubricating oil used in the first embodiment was composed of 93 to 98.9 t% of alkyl diphenyl ether oil as a base oil and 1 to 5 wt% of molybdenum disulfide as an additive. And 0.1 to 2% by weight of an antioxidant as an additive.

According to the experiments of the inventors, surprisingly, when 1 to 5 wt% of molybdenum disulfide was added as an inorganic compound to alkyldiphenyl ether oil, the lubricating oil at high temperature use was It was found that the oxidation resistance of the steel was significantly improved. However, when the amount of molybdenum disulfide is less than 1 wt%, the effect of improving oxidation resistance is reduced, while when the amount is more than 5 wt%, lubricating oil quality (homogeneity) is reduced. Decreased.

On the other hand, according to experiments by the inventors, when an alkyl diphenyl ether oil is added with graphite as an inorganic compound, the oil film thickness is the same as that of molybdenum disulfide. Although the increase was observed, the oxidation resistance was inferior.

[Base oil]

Alkyl diphenyl ether is based on either dialkyl diphenyl ether or monoalkyl diphenyl ether and has a viscosity of 80 to 150 mm ² / s. (40 ° C)

C additive]

Contains molybdenum disulfide (average particle size 0.5 μm) for oil film retention. Molybdenum disulfide is preferred because it also acts as a solid lubricant.

Antioxidants are aromatic amines or phenols, for example, For example, phenyl-α-naphthylamine, phenothiazine, and phenol-based 2,6-di-tert-butylparacresol, 2,6-di-phenylamine — Tert-butyl ether, 6-tert-butyl 10-cresol and the like.

As described above, the shaft pin 11a, 12a, 15a, 15b, 19a, the bearing part, force latch 11, latch 12, lever 13, Lubricating oil of phenyl ether type, which has not been used as lubricating oil for conventional circuit breakers, is applied to the sliding part of toggle link 15 so that lubricating oil can be easily applied in a short time. As a result, it is possible to provide a circuit breaker that is excellent in lubricating oil heat resistance and oxidation resistance and has stable operation while having high circuit breaker assembly efficiency.

Embodiment 2

Hereinafter, a second embodiment of the present invention will be described.

In the second embodiment, the circuit breaker is composed of a shaft pin 11a, 12a, 15a, 15b, 19a, a bearing portion, a force barrier 11, a latch 12, Apply the following grease to the sliding part by lever 13 and toggle link 15 as shown below. Grease is a semi-solid lubricant consisting of a liquid lubricant (base oil) and a thickening agent.

C lubricant]

The lubricant used in the present embodiment is composed of 77 · 0 to 97 · 8 wt% of an alkyldiphenyl ether oil as a base oil, and a urea-based powder as a thickening agent. ~ 20 wt%, 0.2 to 3 wt% of antioxidant as an additive, and 88.0 to 94.0 wt% of alkyldiphenyl ether oil as a base oil, preferably The amount of urea is 5 to 10 wt% as a thickener, and the amount of antioxidant is 1.0 to 2.0 wt% as an additive. According to experiments by the inventors, it was found that phenyl ether-based grease, particularly grease using urea-based stone, had excellent oxidation resistance at high temperatures. This is because the urea-based stone has excellent shape retention at high temperatures, and is less likely to lose its shape and has a smaller film thickness than general-purpose lithium-based stone, which has poor heat resistance. It is presumed to be bad. That is, it is presumed that when the thickness of the applied film is large, the actual volume becomes large, so that the oxidation time is lengthened and the oxidation resistance is improved. It is also assumed that the thicker the oxide film, the easier the molecules that make up the base oil to move, and the better the oxidation resistance as compared to a thin film in which the molecules tend to stay.

[Grease]

Grease is a grease containing alkyl diphenyl ether oil as a base oil and an agent to increase rare earth stones. Alkyl diphenyl ether oils contain either dialkyl diphenyl ether or monoalkyl diphenyl ether as a main component.

[Additive ]

Antioxidants are aromatic amines or phenols. For example, amines include phenyl or naphthylamine, phenothiazine, and phenyl. For ethanol, 2,6-di-ert: butyl paracresol, 2,6-di-tert-butyl phenol, 6-tert-butyl-10-cresol And so on.

As described above, the shaft pin 11a, 12a, 15a, 15b, 19a, the bearing, the force indenter 11, the latch 12, the lever 13, and the '' The sliding part of toggle link 15 was coated with phenyl ether-based grease, which was not conventionally used as lubricating oil for circuit breakers. (Because it is applied to the engaging part with the lever 13), it has excellent lubrication performance under high load and excellent oxidation resistance of lubrication, and stable operation for a long time. Circuit breakers can be provided. Also, since the grease has excellent lubrication performance under a high load, it is preferable to use the grease as a lubricant between the insulating holder holding the movable contact and the base of the circuit breaker. In this case, the lubricant of the mechanism and the lubricant between the insulating holder and the base can be used in common, so that the coating efficiency is good and the characteristics change with each other as in the case of using lubricants of different components. Nor. In addition, lubricating oil (for example, the lubricating oil described in the first embodiment) is lubricated into the sliding part of the bearing part by the shaft pins lla, 12a, 15a, and 19a of the mechanism. In this case, work efficiency is excellent.

Example

Hereinafter, embodiments of the present invention will be described in more detail with reference to Examples. Example 1

In order to simulate the lubricating oil between the mechanical parts and the sticking during grease deterioration, various lubricants as shown in Table 1 (lubricating oil) and Table 2 (grease) below were oxidized. Shearing between the coated iron substrates and evaluation of the shearing force after high-temperature holding were performed.

[Sample substrate]

Substrate 1: 10 mm long, 1 Omm wide, 2 mm thick

Board 2: 30 mm long, 30 mm wide, 2 mm thick

Cold rolled steel plate (SPCC-SD)

Nitriding treatment: Hold at 580 ° C in a mixed gas atmosphere of ammonia, carbon dioxide and nitrogen for 1.5 hours to form a nitrided layer with a thickness of 10 to 15 µm.

After the nitriding treatment, the following steam treatment is performed.

Steaming: 5 5 0 ° C, held in a water vapor 0 5 hours, to form a F e ₃ 0 ₄ film having a thickness of 2 〃 m nitride layer.

[lubricant ]

• Lubricant

(Refined lubricating oil: Comparative example) A conventional lubricating oil having the following composition was used as a comparative example in this experiment. AO 1: Alphaolefin base oil 99.5 wt%, phenolic antioxidant 0.5 wt% 0

(Phenyl ether lubricating oil)

B 01: Alkyl diphenyl base oil 99.5 wt% _N phenol antioxidant 0.5 wt%

B 02: Alkyl diphenyl ether base oil 98.5 wt%, molybdenum disulfide 1.0 wt%, phenolic antioxidant 0.5 wt%

B03: Alkyl diphenyl ether base oil 97.0 wt%, molybdenum disulfide 2.5 wt%, phenolic antioxidant 0/5 wt%

B04: Alkyl diphenyl ether base oil 94.5 wt%, molybdenum disulfide 5 wt%, phenolic antioxidant 0.5 wt%

B 05: Alkyl diphenyl ether base oil 97.0 wt%, graphite 2.5 wt%, phenolic antioxidant 0.5 wt%

table 1

N o Base oil additive Antioxidant

A 0 Ale-refractive phenol-based acid

1-base base oil 9 9 Antioxidant 0.5

. 5 wt% w t%

B 0 Alkyl diphenol-based acid

1 Nylether-based antioxidant 0.5

Base oil 99.5 wwt%

ΐ%

B 0 Alkyl diphenyl molybdenum phenol-based acid

2 Nitroether type anti-denaturation agent 0.5

1.0 w t% w t%

9 8.5 w t%

B 0 Alkyl diphenyl disulfide Molybdenum phenolic acid

3 Nyl ether type anti-denaturation agent 0.5

Base oil 2.5 w t% w t%

9 7.0 w t%

B 0 Alkyl diolefine Molybdenum phenolic acid

4 'Nyl ether type anti-denaturation agent 0.5

Base oil 5.0 w t% w t%

94.5 w ΐ% B 0 Alkyl digraphite phenolic acid

5 Nyl ether-based 2.5 wt% antioxidant 0.5

Base oil w t%

9 7.0 w t%

• Grease

(α-refined grease)

A conventional grease having the following composition was used as a comparative example in this experiment.

CO 1: Alphaolefin base oil 84.5 wt%, lithium stone 7.0 wt%, molybdenum disulfide 8.0 wt%, phenolic antioxidant 0.5 wt%

(Phenyl ether-based grease)

D O 1: Alkyl diphenyl ether base oil 88.0 wt%, lithium stone 10.0 wt%, antioxidant 2.0 wt%

D O 2: Alkyl diphenyl ether base oil 88.0 wt%, urea stone 10.0 wt%, antioxidant 2.0 wt%

Table 2

[140 ° C thermal degradation test (shear test)] (test conditions) Apply various lubricants between the sample substrates 1 and 2 and keep them in a thermostat at 140 ° C in the atmosphere. The application amount is 17 mg for oil and 7 mg for grease. Predetermined time (1, 3, 5, 7, 10, 20, 30, 30, 50 ヽ 70, 100, 200, 300, 500, 700, 700 After a lapse of 0, 2000, and 30000 hours, the shearing force between the removed sample substrates was measured. Shear force is the sticking force due to the oxidative deterioration of the lubricant between sample substrates

(Evaluation criteria)

The shear force was measured using a Shimadzu Precision Universal Testing Machine AG-100B. The shearing force is the maximum force required to fix the substrate 1 and to slide the substrate 2 against the substrate 1 in the surface direction.

Then, when a lubricant is lubricated or applied to the mechanism of the circuit breaker, it is not more than a predetermined shear force that allows the mechanism to operate smoothly (2 N or less for the circuit breaker corresponding to Example 1). Those that passed were considered to be acceptable and within the life span. Here, the service life according to the test results refers to a range in which the lubricant can obtain desired lubricating properties with respect to heat resistance and oxidation resistance.

[Test results]

Fig. 3 shows the results of a thermal degradation test (life test) on lubricating oil. FIG. 3 shows the relative relationship of the results of the thermal degradation test for each sample, with the life of Comparative Example A01 set to 1. Figure 4 shows the results of the grease thermal degradation test (life test). FIG. 4 shows the relative relationship of the results of the thermal degradation test for each sample, with the life of Comparative Example B01 set to 1.

Hereinafter, each sample will be described.

• Lubricant

(α-refined lubricating oil)

AO 1: Alphaolefin base oil 99.5 wt%, phenol oxidation 0.5 wt% of the inhibitor was inferior in lubricity and oxidation resistance.

(Phenyl ether lubricant)

B 01: 99.5 wt% of alkyl diphenyl ether base oil and 0.5 wt% of phenolic antioxidant were inferior in lubricity and slightly superior in oxidation resistance.

B02: Alkyl diphenyl ether base oil 98.5 wt%, molybdenum disulfide 1.0 wt%, phenolic antioxidant 0.5 wt% have excellent lubricating properties. It was also excellent in oxidation resistance.

B03: 97.0 wt% of alkyl diphenyl ether base oil, 2.5 wt% of molybdenum disulfide, and 0.5 wt% of phenolic antioxidant have excellent lubricity. At the same time, it was also excellent in oxidation resistance.

B04: Alkyl diphenyl ether base oil 94.5 wt%, molybdenum disulfide 5 wt%, and phenolic antioxidant 0.5 wt% are superior in lubricity. In addition, it had excellent oxidation resistance.

B05: 97.0 wt% of alkyl diphenyl ether base oil, 2.5 wt% of graphite, and 0.5 wt% of phenolic antioxidant have excellent lubricity. The oxidation resistance was slightly better.

The above results are summarized. B01 to B05, in which the base oil is an alkyl diphenyl ether, compared to A01 to which the base oil of the comparative example was an olefin-based system to which only an antioxidant was added, It was excellent. B01, in which the base oil was an alkyl diphenyl ether and only an antioxidant was added, exhibited a lifespan approximately 5 times that of A01, and B02 to which molybdenum disulfide was added. 304 has a lifetime of about 20 times that of 01 and about 4 times that of B01, and it has been found that it has extremely excellent oxidation resistance. In contrast, the life of B05 added with graphite instead of molybdenum disulfide was equivalent to that of BO1, and no life extension effect was observed. That is, antioxidants were added. Arukirujifu enyl ethers, particularly also added a predetermined amount of disulfide mode Li Buden after nitriding treatment, at high temperatures the use of F e ₃ 0 ₄ film formed iron based material with a thickness of this nitride layer surface It has excellent oxidation resistance.

From this, the following is considered.

Arukirujifu phenyl ether antioxidant is added, small, and this to undergo chemical reactions Ya catalysis of some kind by F e ₃ 0 ₄ film formed iron based material having a thickness of 2 m on the nitride layer surface It is compatible with the iron-based material when used at high temperatures.

In addition, by adding molybdenum disulfide powder having a large lipophilicity and a large specific surface area to the alkyl diphenyl ether, the oil film becomes thicker and the actual volume becomes larger, so that the oxidation time becomes longer. That is, it is assumed that the oxidation resistance is further improved. In addition, small, and this undergoing chemical reaction or catalytic action of some kind by F e ₃ 0 ₄ film shape formed iron based material with a thickness of the nitrided layer surface rather, the said iron-based material at a high temperature using Is presumed to be compatible. If the oil film is thicker, the molecules that make up the oil move more easily, and the surface layer that is oxidized compared to a thin film (for example, an oil film without additives) where molecules tend to accumulate. It is presumed that the oxidation resistance is improved because the antioxidant easily moves to the surface. However, if the amount of molybdenum disulfide is less than 1 wt%, the above-mentioned effect of improving the oxidation resistance is reduced, but this is considered to be because the oil film has become thinner. %, The lubricating oil quality (homogeneity) is reduced, probably because the dispersion stability of molybdenum disulfide decreases.

On the other hand, when graphite was added as an inorganic compound, an increase in the oil film thickness was observed as in the case of molybdenum disulfide, but the oxidation resistance was poor. This forms the F e ₃ 0 ₄ film having a thickness of 2 〃 m nitride layer surface In contrast to silicon oxide, which is mainly non-metallic impurities contained in molybdenum disulfide, has undergone some chemical reaction or catalysis by iron-based materials, but is contained in graphite It is presumed that the impurities contained include iron and iron compounds having a metal catalytic action.

• Grease

(Foreground grease)

CO 1: Alphaolefin base oil 84.5 wt%, lithium stone 7.0 wt%, molybdenum disulfide 8.0 wt%, phenolic antioxidant 0.5 wt% of the agent was excellent in lubricity but inferior in oxidation resistance.

(Phenyl ether-based grease)

DO 1: alkyl diphenyl ether base oil 88.0 wt%, lithium stone 10.0 wt%, and antioxidant 2.0 wt% are excellent in lubricity and slightly excellent in oxidation resistance I was

D O 2: Alkyl diphenyl ether base oil 88.0 wt%, urea stone 10.0 wt%, and antioxidant 2.0 wt% have excellent lubricity.

The oxidation resistance was also excellent.

The above results are summarized. DO 1 and DO 2 have a lifespan 3 to 5 times that of CO 1, and include urea as a thickening agent. D 0 2 contains lithium as a thickening agent. The service life was about 1.7 times longer than that of DO 1 including this. From this, the following can be considered.

Grayed lease to Arukirujifu phenyl ether-based base oil antioxidant is added, F e ₃ 0 ₄ layer some kind of chemical by ferrous material to form a thick 2 〃 m nitride layer surface It is less susceptible to reaction and catalysis, and is compatible with the iron-based material when used at high temperatures.

In addition, urea stone is inferior in heat resistance due to its excellent shape retention at high temperatures. Compared to general-purpose lithium stone, its shape is less likely to collapse, its thickness is not thinner, and its actual volume is larger, so oxidation time is longer and oxidation resistance is improved. It is presumed. It is also assumed that the thicker the film, the more easily the molecules composing the base oil move, and the better the oxidation resistance as compared to a thin film in which the molecules tend to stay.

Therefore, it is preferable that the base oil is alkyl diphenyl ether and the thickener is urea-based stone. Example 2.

Under the following conditions, the lubricating oil and grease as shown in Table 3 below were compared in terms of lubrication characteristics (load-bearing performance).

Table 3

(Test condition)

While pressing a rotating steel ball against a 39.5 mm diameter fixed steel ball coated with lubricant with a load of 0.049 MPa, the 75 Orp. Rotating at m. and obtaining the hydraulic load that does not cause seizure The acceptable limit load was determined using a Soda type four-ball testing machine.

(Test results)

Fig. 5 shows the test results of the pass limit load.

• Lubricant

B 03: Alkyl diphenyl ether base oil 97.0 wt%, disulfide The acceptable limit load was 0.2 Mpa for the lubricating oil containing 2.5 t% of phenol-based antioxidant and 0.5 wt% of lithium.

• Grease

DO 2: Alkyl diphenyl ether base oil 88.0 wt%, grease containing 10.0 wt% of urea stone and 2.0 wt% of antioxidant have a pass limit load of 0.3. It was 4 MPa.

From the above, it can be seen that grease is superior in load resistance when comparing the load resistance of grease with lubricating oil having excellent oxidation resistance. Therefore, if the required load performance of the circuit breaker mechanism is large, it is preferable to apply grease. Industrial Possibilities'

In the circuit breaker of the present invention, the switching mechanism for opening and closing the movable contact is housed in the insulating case, so that the operation is stable even at high temperature and high humidity and is suitable.

Claims

The scope of the claims

1. It has an insulating case, an opening / closing mechanism that is housed in the insulating case and opens and closes the movable contact, and an engaging portion that engages with the opening / closing mechanism. A releasing mechanism for releasing the engagement of the engaging portion and separating the movable contact from the fixed contact, wherein a part of the opening / closing mechanism includes iron or an iron compound. A circuit breaker made of material,

A circuit breaker, characterized in that a phenyl ether-based lubricant to which an antioxidant is added is provided on the sliding portion of the material containing iron or an iron compound.

2. The sliding portion of the material containing iron or iron compound, F e ₃ 0 ₄ layer or circuit breaker as in claim 1, wherein said that you main tree key film is provided.

3. The circuit breaker according to claim 1 or 2, wherein the phenyl ether-based lubricant is a phenyl ether-based oil.

4. The circuit breaker according to claim 3, wherein molybdenum disulfide is added to the phenyl ether-based oil.

5. The circuit breaker according to claim 4, wherein the amount of molybdenum disulfide is 1 to 5 wt%.

6. The circuit breaker according to claim 1, wherein a phenyl ether-based oil is provided at an engagement portion between the latch portion and the urging portion.

7. The phenyl ether-based lubricant according to claim 1 or 2, wherein the phenyl ether-based lubricant is a phenyl ether-based grease containing urea-based stone as a thickening agent. Circuit breaker.