JP2014228059A - Rolling bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolling bearing capable of preventing peeling on a ferrous metal member surface due to hydrogen brittleness even under a severe environment.SOLUTION: A rolling bearing 1 includes a plurality of bearing members composed of ferrous metal, and a lubricant composition 7 lubricated on the metal contact surface of each bearing member. The lubricant composition 7 is grease containing base oil and amine salt of alkyl aromatic sulfonic acid, and not containing inorganic acid alkali metal salt or alkali earth metal salt. The amine salt of the alkyl aromatic sulfonic acid is 0.1-10 pts.wt. with respect to 100 pts.wt. of the total amount of the base oil and thickening agent.

Description

  TECHNICAL FIELD The present invention relates to a rolling bearing, and in particular, a rolling bearing (grease lubrication) used for an automotive electrical component / auxiliary such as an alternator, an electromagnetic clutch for a car air conditioner, an intermediate pulley, an electric fan motor, an industrial machine, an electric vehicle drive, and the like. The present invention relates to a rolling bearing (grease lubrication) used for a motor of the present invention, a rolling bearing (oil lubrication) used for a speed increaser such as a wind power generator and a reduction gear for a construction machine.

  Electrical components and accessories in automobiles, motors in industrial machines, drive motors for electric cars and hybrid cars are required to be smaller, have higher performance, and have higher output year by year, and use conditions are becoming stricter. For these, rolling bearings are used, and grease is mainly used for lubrication. However, due to severe conditions of use, such as high-speed rotation at high temperatures, specific peeling with a change in white structure occurs early on the rolling surface (bearing steel) of a rolling bearing, which is a problem. . In addition, these specific separations are also evident in rolling bearings used in oil lubrication, such as rolling bearings for reduction gears for construction machinery and speed increasers for wind power generators.

  This specific delamination is delamination starting from the inside of the rolling contact surface as in the case of delamination caused by normal metal fatigue. However, as one of the short-lived factors, a fracture phenomenon due to hydrogen embrittlement is considered. ing. As a method for preventing such a specific peeling phenomenon accompanied by a white tissue change that occurs at an early stage, for example, a method in which a passivating agent is blended in a grease composition is known (see Patent Document 1). A method of blending bismuth dithiocarbamate with a grease composition is known (see Patent Document 2). In addition, since the bearing rolling surface is made of ferrous metal bearing steel, considering the mutual solubility with iron, the grease composition contains metal powder such as aluminum, silicon, titanium, tungsten, molybdenum, chromium, cobalt, etc. A method of blending is also proposed (see Patent Document 3).

  In addition, as a grease composition that can improve fretting resistance and reduce the amount of wear, base grease includes tribasic calcium phosphate, petroleum sulfonic acid, alkyl aromatic sulfonic acid, salicinate, alkali metal salt of phenate, alkaline earth metal A blend of at least one selected from the group consisting of a salt, an amine salt and a zinc salt has been proposed (see Patent Document 4).

JP-A-3-210394 JP-A-2005-42102 JP 2008-266424 A JP 2011-184680 A

  However, in electrical components and accessories in automobiles, motors in industrial machines, and the like, bearings are being further miniaturized in accordance with recent miniaturization. Therefore, the contact surface pressure applied to the members constituting the bearing tends to increase. In addition, the speed of rotation of these devices has been increased, and high-speed operation, rapid deceleration operation, rapid acceleration operation, and sudden stop tend to be frequently performed. An increase in the surface pressure between the rolling elements and the raceway or an increase in slip due to sudden acceleration / deceleration easily causes oil film breakage (poor lubrication) at the portion. Under such a severe environment, the method of adding a passivating agent or bismuth dithiocarbamate as in conventional Patent Document 1 and Patent Document 2 is insufficient as a measure for preventing the above-described peeling phenomenon. ing.

  Concerning construction machines, those used for construction work under cold or scorching conditions will tend to increase in the future. For wind turbine generators, installation has been actively considered in the past in view of a decrease in the degree of freedom of installation location due to further increases in future needs, energy conversion trends, and progress in wind condition analysis. It is thought that the number of cases where it was installed on the ocean or in mountainous areas (highlands) that had not been increased will increase. Under these circumstances, it is desired to prevent the above-described peeling phenomenon even in a harsh use environment that has been difficult to imagine in the past. In particular, since access to the apparatus is expected to be difficult, the need to prevent the above-described peeling phenomenon for a long period of time and reduce the frequency of maintenance is also expected to increase.

  As the oil film thickness on the bearing sliding surface becomes thinner, the peeling phenomenon is more likely to occur. In particular, in the above-mentioned severe environment, the lubrication of the sliding surface becomes the boundary lubrication condition, and the oil film thickness is on the order of submicron (0.1 μm or less). In such an environment, for example, as in Patent Document 3, even when using a metal powder having a certain mutual solubility with iron, depending on the particle diameter or the like, it is not possible to sufficiently intervene on the sliding surface, and the effect is effective. May not be obtained.

  Moreover, the grease composition described in Patent Document 4 is intended to improve the fretting resistance and reduce the amount of wear, and is not intended to prevent the peeling phenomenon. For this reason, the said peeling phenomenon cannot be prevented and it may have a bad influence depending on the specific combination of an essential component.

  The present invention has been made to cope with such a problem, and an object of the present invention is to provide a rolling bearing capable of preventing peeling on the surface of an iron-based metal member due to hydrogen embrittlement even under a severe environment.

  The rolling bearing of the present invention is a rolling bearing having a plurality of bearing members made of iron-based metal and a lubricant composition that lubricates a metal contact surface of each bearing member, and the lubricant composition is a base oil. And an amine salt of an alkyl aromatic sulfonic acid, which does not contain an alkali metal salt or an alkaline earth metal salt of an inorganic acid, and the amine salt of the alkyl aromatic sulfonic acid is the lubricating oil. In this case, it is contained in an amount of 0.1 to 10% by weight based on the whole lubricating oil, and in the case of the grease, 0.1 to 10% with respect to 100 parts by weight of the total amount of the base oil and the thickener. A part by weight is included.

  The amine constituting the amine salt of the alkyl aromatic sulfonic acid is an amine having a plurality of amino groups. In particular, the amine salt of the alkyl aromatic sulfonic acid is diethylene triamine salt or ethylenediamine salt of dinonylnaphthalene sulfonic acid.

  The lubricant composition is grease, and the base oil contains at least one oil selected from alkyl diphenyl ether oil, poly-α-olefin oil (hereinafter also referred to as “PAO”) and ester oil, The thickener contains at least one urea compound selected from an aliphatic diurea compound, an alicyclic diurea compound, and an aromatic diurea compound. Further, when the lubricant composition is a grease, it further includes zinc dithiophosphate.

  The lubricant composition is a lubricating oil, and the base oil contains at least one oil selected from mineral oil, highly refined mineral oil, and water-soluble lubricating oil.

  The rolling bearing of the present invention has a plurality of bearing members made of an iron-based metal and a lubricant composition for lubricating the metal contact surface of each bearing member, and the lubricating composition is an amine salt of an alkyl aromatic sulfonic acid. Therefore, even when the oil film becomes thin under severe conditions, peeling on the rolling surface due to hydrogen embrittlement can be effectively prevented. As a result, the bearing life is excellent, and it can be suitably used as a rolling bearing for automotive electrical parts such as alternators, electromagnetic clutches for car air conditioners, intermediate pulleys, and electric fan motors, and auxiliary machines. Moreover, it can utilize suitably also as a bearing used by oil lubrication, such as a bearing for the reduction gear for construction machines, and the gearbox of a wind power generator.

It is sectional drawing of the deep groove ball bearing which is an example of the rolling bearing of this invention. It is sectional drawing of the motor using the rolling bearing of this invention. It is sectional drawing of the speed up gear using the rolling bearing of this invention.

  In rolling bearings, in order to prevent peeling on the rolling surface (the surface of ferrous metal member) due to hydrogen embrittlement, as a result of intensive investigation of lubricating oil or grease used for lubrication, an amine salt of alkyl aromatic sulfonic acid is essential. It has been found that by blending as an additive, separation on the rolling surface due to hydrogen embrittlement can be effectively prevented.

  In rolling bearings, when rolling metal and metal members such as rolling elements and race rings, rolling elements and cages are in rolling contact and sliding while in contact with lubricating oil or grease, in the contact surface between the iron metal members, There may be a boundary lubrication condition in which the oil film is almost lost and the surfaces of the metals are in direct contact with each other. In this way, even when the oil film becomes thin under severe conditions (boundary lubrication conditions) on the sliding surface, the frictional wear surface at the contact portion or the iron-based metal nascent surface exposed due to wear on the surface of the alkyl aromatic sulfonic acid The amine salt is adsorbed and a stable film is formed. This action prevents direct contact between the new ferrous metal surface and the lubricating oil or grease, suppresses the generation of hydrogen due to the decomposition of the lubricating oil or grease, prevents peculiar peeling due to hydrogen embrittlement, and the life of the rolling bearing. Can be extended. The present invention is based on these findings, and in particular, in rolling bearings, the present invention can be suitably used for lubrication in which the environment in which the ferrous metal member and the lubricating oil or grease are in contact with the boundary lubrication condition on the ferrous metal member surface.

  The aspect of the lubricant composition used for the rolling bearing of the present invention includes (1) a lubricating oil essentially comprising a base oil and an amine salt of an alkyl aromatic sulfonic acid, and (2) a base oil and a thickener. There are two types of greases, which are essentially composed of an amine salt of an alkyl aromatic sulfonic acid. In either case, the inorganic acid alkali metal salt and the inorganic acid alkaline earth metal salt are not included. Here, examples of the inorganic acid include phosphoric acid (orthophosphoric acid), hydrochloric acid, nitric acid, sulfuric acid, boric acid and the like. Examples of the alkali metal and alkaline earth metal include lithium, sodium, potassium, calcium, strontium, barium and the like. Is mentioned. Specific examples include tricalcium phosphate (calcium salt of orthophosphoric acid).

As the sulfonic acid constituting the amine salt of the alkyl aromatic sulfonic acid used in the present invention, the aromatic group may be either a monocyclic or polycyclic condensed ring, and examples thereof include benzene, naphthalene, anthracene, phenanthrene and the like. . Among these, since it is excellent in thermal stability, an alkylbenzene sulfonic acid represented by the following formula (1) in which the aromatic group is benzene, and an alkyl naphthalene sulfonic acid represented by the following formula (2) in which the aromatic group is naphthalene. Is preferred. Alkyl naphthalene sulfonic acid is particularly preferable.

  In the formulas (1) and (2), R and R ′ are each an alkyl group (aliphatic hydrocarbon group), and n is an integer of 1 to 3. 1-30 are preferable, as for carbon number in R and R ', 6-18 are more preferable, and 8-10 are especially preferable.

  Examples of the amine constituting the amine salt of the alkyl aromatic sulfonic acid include ethylamine, trimethylamine, ethylenediamine, diethylenetriamine and the like. Among these, it is preferable to use ethylenediamine or diethylenetriamine having a plurality of amino groups. When ethylenediamine or diethylenetriamine is used as the amine, it is possible to prevent exposure of the new iron-based metal surface by sandwiching iron ions by chelating action.

The amine salt of alkyl aromatic sulfonic acid may be used alone or in combination of two or more. The amine salt of alkyl aromatic sulfonic acid is preferably liquid at room temperature and operating temperature. Further, it may be dispersed in an aliphatic solvent, mineral oil or the like. By using a liquid material, even when the oil film of the sliding part becomes thin under severe conditions, it is easy to enter the sliding part and to form a film. The kinematic viscosity of the amine salts of alkyl aromatic sulfonic acid, preferably 10 to 100 mm ² / s at 100 ° C., more preferably 20~85mm ² / s at 100 ° C..

  Examples of commercially available amine salts of alkyl aromatic sulfonic acids include, for example, King's NA-SUL DTA (diethylenetriamine salt of dinonylnaphthalenesulfonic acid), NA-SUL EDS (ethylenediamine salt of dinonylnaphthalenesulfonic acid), etc. Is mentioned.

  In addition, when an alkali metal salt or alkaline earth metal salt of the sulfonic acid is used in place of the amine salt of the alkyl aromatic sulfonic acid, peeling on the rolling surface due to hydrogen embrittlement, as shown in Comparative Examples described later, etc. It cannot be prevented and may have adverse effects. For this reason, it is preferable not to contain the alkali metal salt or alkaline-earth metal salt of alkyl aromatic sulfonic acid.

  When using the said lubricant composition as lubricating oil, the compounding ratio of the amine salt of alkyl aromatic sulfonic acid shall be 0.1 to 10 weight% with respect to the whole lubricant composition. Within this range, unique peeling due to hydrogen embrittlement can be prevented. If it exceeds 10% by weight, the reactivity with iron becomes so high that corrosion wear occurs and the life of occurrence of peeling cannot be extended. Preferably it is 0.3 to 10 weight%, More preferably, it is 0.3 to 5 weight%, More preferably, it is 2 to 5 weight%.

  When using the said lubricant composition as grease, the compounding ratio of the amine salt of alkyl aromatic sulfonic acid shall be 0.1-10 weight part with respect to 100 weight part of total amounts of a base oil and a thickener. Within this range, unique peeling due to hydrogen embrittlement can be prevented. If the amount exceeds 10 parts by weight, the peeling occurrence life cannot be extended due to reasons such as excessive reactivity with iron and corrosive wear. Preferably it is 0.3-10 weight part, More preferably, it is 0.3-5 weight part, More preferably, it is 2-5 weight part.

  The base oil that can be used in the lubricant composition is not particularly limited, and those commonly used in the field of ordinary lubricating oil / grease can be used. For example, mineral oil such as spindle oil, refrigerator oil, turbine oil, machine oil, dynamo oil, highly refined mineral oil, liquid paraffin oil, polybutene oil, GTL oil synthesized by Fischer-Tropsch method, PAO, alkylnaphthalene oil, alicyclic ring Hydrocarbon synthetic oils such as formula compounds, or natural oils, polyol ester oils, phosphate ester oils, polymer ester oils, aromatic ester oils, carbonate ester oils, diester oils, polyglycol oils and other ester oils, silicone oils And non-hydrocarbon synthetic oils such as polyphenyl ether oil, alkyl diphenyl ether oil, alkyl benzene oil, and fluorinated oil. Moreover, water-soluble lubricating oils, such as water-glycol type hydraulic oil, are mentioned. These may be used alone or in combination of two or more.

  When using the said lubricant composition as lubricating oil, it is preferable to use at least 1 oil chosen from mineral oil, highly refined mineral oil, and water-soluble lubricating oil among the said base oil. Highly refined mineral oil can be obtained by, for example, catalytic hydrothermal decomposition of slag wax obtained from the residue of vacuum distillation and synthesizing. Moreover, the GTL oil etc. which are synthesize | combined by the Fischer-Tropsch method are mentioned. The highly refined oil preferably has a sulfur content of less than 0.1% by weight, more preferably less than 0.01% by weight.

The kinematic viscosity of the base oil (in the case of a mixed oil, the kinematic viscosity of the mixed oil) is preferably 10 to ²⁰⁰ mm ² / s at 40 ° C. More preferably, it is 10-100 mm < ² > / s, More preferably, it is 30-100 mm < ² > / s.

  When the lubricant composition is used as a grease, it is preferable to use at least one oil selected from alkyl diphenyl ether oil, PAO and ester oil among the base oils because of excellent heat resistance and lubricity. PAO is usually a mixture of oligomers or polymers of α-olefins or isomerized α-olefins. Specific examples of the α-olefin include 1-octene, 1-nonene, 1-decene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1 -Nonadecene, 1-eicosene, 1-docosene, 1-tetradocosene and the like can be mentioned, and usually a mixture thereof is used.

  When the lubricant composition is used as a grease, a thickener is further added. The thickener is not particularly limited, and a common one used in the field of grease can be used. For example, soap-type thickeners such as metal soaps and composite metal soaps, and non-soap-type thickeners such as benton, silica gel, urea compounds and urea / urethane compounds can be used. Examples of the metal soap include sodium soap, calcium soap, aluminum soap, and lithium soap. Examples of the urea compound and urea / urethane compound include diurea compounds, triurea compounds, tetraurea compounds, other polyurea compounds, and diurethane compounds. Among these, it is preferable to use a urea compound that is excellent in heat durability and excellent in intervening property and adhesion to the sliding portion.

  A urea compound is obtained by reacting a polyisocyanate component and a monoamine component. Examples of the polyisocyanate component include phenylene diisocyanate, tolylene diisocyanate, diphenyl diisocyanate, diphenylmethane diisocyanate, octadecane diisocyanate, decane diisocyanate, and hexane diisocyanate. Moreover, an aliphatic monoamine, an alicyclic monoamine, and an aromatic monoamine can be used for a monoamine component. Aliphatic monoamines include hexylamine, octylamine, dodecylamine, hexadecylamine, octadecylamine, stearylamine, oleylamine and the like. Examples of the alicyclic monoamine include cyclohexylamine. Aromatic monoamines include aniline, p-toluidine and the like.

  Among these urea compounds, since they are particularly excellent in heat resistance durability, diurea compounds using aromatic diisocyanates as polyisocyanate components, for example, aromatic diurea compounds using aromatic monoamines as monoamine components, aliphatic monoamines are used. It is preferable to use an aliphatic diurea compound or an alicyclic diurea compound using an alicyclic monoamine.

  Base grease can be obtained by blending a base oil with a thickener such as a urea compound. A base grease using a urea compound as a thickener is prepared by reacting the polyisocyanate component and the monoamine component in a base oil. The blending ratio of the thickener in the base grease is 1 to 40% by weight, preferably 3 to 25% by weight. If the content of the thickener is less than 1% by weight, the thickening effect is reduced, making it difficult to make a grease. If the content exceeds 40% by weight, the obtained base grease becomes too hard and the desired effect is difficult to obtain. Become.

  As a method for preparing grease, first, a method in which an amine salt of an alkylaromatic sulfonic acid is blended with a base oil, a thickener is prepared using this base oil, and a method in which a dispersion is added to a grease after it has been prepared Any of these may be used. Since the amine salt of the alkyl aromatic sulfonic acid contains an amino group, the base salt is prepared by reacting the polyisocyanate component and the monoamine component in the base oil, and then the amine salt of the alkyl aromatic sulfonic acid is added. Is a preferred method.

  In the case of the above grease, the penetration (JIS K 2220) is preferably in the range of 200 to 350. When the consistency is less than 200, oil separation is small and there is a risk of poor lubrication. On the other hand, if the consistency exceeds 350, the grease is soft and easily flows out of the bearing, which is not preferable.

  The lubricant composition may contain a known additive other than the amine salt of an alkyl aromatic sulfonic acid, if necessary, as long as the object of the present invention is not impaired. Examples of additives include antioxidants such as organic zinc compounds, amines, and phenolic compounds, metal deactivators such as benzotriazole, viscosity index improvers such as polymethacrylate and polystyrene, molybdenum disulfide, and graphite. Examples thereof include solid lubricants, metal sulfonates, rust inhibitors such as polyhydric alcohol esters, oil agents such as esters and alcohols, and other antiwear agents. These can be added alone or in combination of two or more. Further, in the present invention, even when an organic molybdenum compound such as molybdenum dithiophosphate and molybdenum dithiocarbamate is not blended, peeling on the rolling surface due to hydrogen embrittlement can be prevented.

  In the case of the grease, it is preferable to include at least one antioxidant selected from a phenol-based antioxidant, an amine-based antioxidant and zinc dithiophosphate. Among these, zinc dithiophosphate is essential, and it is preferable to use one of a phenolic antioxidant and an amine antioxidant in combination. In particular, it is preferable to use zinc dithiophosphate and a phenolic antioxidant together. Moreover, it is preferable that the mixture ratio of these antioxidants is 0.5-5 weight part in total with respect to 100 weight part of total amounts of a base oil and a thickener.

Examples of zinc dithiophosphate (zinc dithiophosphate; hereinafter referred to as “ZnDTP”) include zinc dialkyldithiodithiophosphate and zinc diaryldithiophosphate represented by the following formulae.

R ¹ in the formula represents a primary or secondary alkyl group having 1 to 24 carbon atoms or an aryl group having 6 to 30 carbon atoms. Examples of R ¹ include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a secondary butyl group, an isobutyl group, a pentyl group, a 4-methylpentyl group, a hexyl group, a 2-ethylhexyl group, and a heptyl group. Octyl group, nonyl group, decyl group, isodecyl group, dodecyl group, tetradecyl group, hexadecyl group, octadecyl group, eicosyl group, docosyl group, tetracosyl group, cyclopentyl group, cyclohexyl group, methylcyclohexyl group, ethylcyclohexyl group, dimethylcyclohexyl Group, cycloheptyl group, phenyl group, tolyl group, xylyl group, ethylphenyl group, propylphenyl group, butylphenyl group, pentylphenyl group, hexylphenyl group, heptylphenyl group, octylphenyl group, nonylphenyl group, decylpheny group Group, dodecylphenyl group, tetradecyl phenyl group, hexadecyl phenyl group, octadecyl phenyl group, and benzyl group. Each R ¹ may be the same or different.

Among these, R ¹ is preferably a primary alkyl group because it is excellent in stability and the like and contributes to prevention of peeling on the rolling surface due to hydrogen embrittlement. Further, when R ¹ is an alkyl group, the greater the number of carbon atoms, the better the heat resistance and the easier it is to dissolve in the base oil. On the other hand, the smaller the number of carbon atoms, the better the abrasion resistance and the like, and the more difficult it is to dissolve in the base oil. As a preferable commercial item of ZnDTP, Adeka Co., Ltd. product: ADEKAKI CLUB Z112 etc. are mentioned, for example.

  The lubricant composition preferably does not contain a solid powder that does not dissolve in the base oil. “Not dissolved in base oil” means, for example, that 0.5% by weight of solid powder is added to the base oil and stirred with respect to the total weight after dissolution, and this is visually observed after being held at 70 ° C. for 24 hours. As a result, it refers to a solid powder in which an insoluble component is precipitated in the base oil. If the insoluble matter is precipitated, the base oil is not transparent, and the solid powder becomes colloidal or suspended, which can be judged visually. Examples of such solid powder include aluminum, silicon, titanium, tungsten, molybdenum, chromium, cobalt, gold, silver, copper, yttrium, zirconium, iridium, palladium, platinum, rhodium, ruthenium, hafnium, tantalum, tungsten, Examples thereof include metal powders such as rhenium and osmium. Even if these metal powders are not blended, the present invention can prevent peeling on a rolling surface due to hydrogen embrittlement by blending an amine salt (liquid) of an alkyl aromatic sulfonic acid.

  The rolling bearing of the present invention has a plurality of bearing members made of an iron-based metal and a lubricant composition that lubricates the metal contact surface of each bearing member. The rolling bearing of the present invention will be described with reference to FIG. FIG. 1 is a cross-sectional view of a deep groove ball bearing. In the rolling bearing 1, an inner ring 2 having an inner ring rolling surface 2a on the outer peripheral surface and an outer ring 3 having an outer ring rolling surface 3a on the inner peripheral surface are arranged concentrically, and the inner ring rolling surface 2a and the outer ring rolling surface 3a A plurality of rolling elements 4 are arranged between the two. The rolling element 4 is held by a cage 5. Further, the axially opposite end openings 8 a and 8 b of the inner and outer rings are sealed by the seal member 6, and at least the rolling element 4 is filled with the above-described lubricant composition 7. The inner ring 2, the outer ring 3 and the rolling element 4 are made of high-carbon chromium bearing steel, which is an iron-based metal, and a lubricant composition 7, which is grease, is interposed on the rolling surface with the rolling element 4 and lubricated.

  In the rolling bearing of the present invention, the ferrous metal material constituting the bearing member is an arbitrary material generally used as a bearing material. For example, the high carbon chromium bearing steel (SUJ1, SUJ2, SUJ3, SUJ4, SUJ5 etc .; JIS G 4805), carburized steel (SCr420, SCM420 etc .; JIS G 4053), stainless steel (SUS440C etc .; JIS G 4303), high speed steel (M50 etc.), cold rolled steel, etc. are mentioned.

  In FIG. 1, a ball bearing is exemplified as the bearing, but the rolling bearing of the present invention is a cylindrical roller bearing, a tapered roller bearing, a self-aligning roller bearing, a needle roller bearing, a thrust cylindrical roller bearing, or a thrust tapered roller bearing other than the above. Also, it can be used for thrust needle roller bearings, thrust spherical roller bearings and the like.

  Since the rolling bearing of the present invention encloses the above-described lubricant composition, it can prevent specific peeling due to hydrogen embrittlement on the rolling surface of the bearing member made of a ferrous metal material, such as under high temperature and high speed. The bearing life is long even under harsh conditions. For this reason, it can be suitably used as a bearing used in high-temperature and high-speed rotation used for motors such as automobile electrical equipment / auxiliary machines and industrial equipment.

  For example, alternators, compressors, electromagnetic clutches for car air conditioners, intermediate pulleys, rolling bearings for automotive electrical equipment and accessories such as electric fan motors, motors for ventilation fans, blower motors for fuel cells, cleaner motors, fan motors, servo motors, stepping motors Motors for industrial machinery such as automobile starter motors, electric power steering motors, steering adjustment tilt motors, blower motors, wiper motors, power window motors and other motors for electrical equipment, drive motors for electric vehicles and hybrid vehicles, etc. It can be suitably used as a rolling bearing.

  An example of a motor to which the rolling bearing of the present invention is applied is shown in FIG. FIG. 2 is a sectional view of the structure of the motor. The motor includes a stator 10 made of a magnet for a motor disposed on the inner peripheral wall of the jacket 9, a rotor 13 around which a winding 12 fixed to the rotating shaft 11 is wound, and a commutator fixed to the rotating shaft 11. 14, a brush holder 15 disposed on an end frame 17 supported by the jacket 9, and a brush 16 accommodated in the brush holder 15. The rotating shaft 11 is rotatably supported by the jacket 9 by the deep groove ball bearing 1 and a support structure for the bearing 1. The bearing 1 is the rolling bearing of the present invention.

  As the motor bearing, in addition to the deep groove ball bearing shown in FIG. 1, angular ball bearings and the above-mentioned bearings can be used. Among these, it is preferable to use a deep groove ball bearing having rotational accuracy at high speed, load resistance, and low cost.

  Moreover, the rolling bearing in which the lubricating oil composition is enclosed can be suitably used as a bearing for a speed reducer for construction machinery or a speed increaser for wind power generation.

  An example of a speed increaser of a wind power generator to which the rolling bearing of the present invention is applied is shown in FIG. FIG. 3 is a cross-sectional view of the speed increaser. The speed increaser main body 21 is provided with a planetary gear mechanism 26 serving as a primary speed increaser and a secondary speed increaser 27 between an input shaft 22 and an output shaft 23. The planetary gear mechanism 26 has a planetary gear 29 installed on a carrier 28 integrated with the input shaft 22, meshes the planetary gear 29 with an internal ring gear 30 and a sun gear 31, and outputs an intermediate shaft with the sun gear 31 as an intermediate output. The shaft 32 is used. The secondary speed increaser 27 includes a gear train that transmits the rotation of the intermediate output shaft 32 to the output shaft 23 via a plurality of gears 33 to 36. The parts constituting the planetary gear 29, the rolling bearing 37 made of bearing steel that supports the planetary gear 29, the ring gear 30, and the gear 33 of the secondary speed increaser 27 are the lubricating oil in the lubricating oil storage tank 24 a in the housing 24. 25. This lubricating oil 25 is the above-described lubricant composition. The lubricating oil reservoir 24a is circulated by circulating oil supply means (not shown) including a pump and piping. Note that the circulating oil supply means is not necessarily provided, and may be an oil bath lubrication type.

  Even in such a speed increaser, specific peeling due to hydrogen embrittlement that occurs on the rolling surfaces of bearings and parts can be prevented over a long period of time, so the life of the speed increaser can be extended. As a result, the maintenance frequency of the wind turbine generator can be reduced.

  The present invention will be specifically described with reference to examples and comparative examples, but is not limited to these examples.

Examples 1 to 8 and Comparative Examples 1 to 10
4,4'-diphenylmethane diisocyanate (hereinafter referred to as MDI) is dissolved in half of the base oil shown in Tables 1 and 2 in the proportions shown in each table, and the remaining half of the base oil is twice the equivalent of MDI. The monoamine was dissolved. Each blending ratio and type are as shown in each table. A solution in which monoamine was dissolved was added while stirring the solution in which MDI was dissolved, and then the reaction was continued with stirring at 100 to 120 ° C. for 30 minutes to produce a diurea compound in the base oil to obtain a base grease. Each additive was added to this at a blending ratio shown in each table and further sufficiently stirred. Thereafter, it was homogenized with three rolls to obtain a test grease. The following 1) to 12) in Table 1 are the same in Table 2 and Table 3.

  The obtained grease was sealed in a rolling bearing and a rapid acceleration / deceleration test was conducted. Test methods and test conditions are shown below. The results are shown in Tables 1 and 2.

<Rapid acceleration / deceleration test>
An alternator, which is an example of an electrical accessory, was simulated, and the grease was enclosed in an inner ring rolling bearing (the inner ring / outer ring / steel ball is bearing steel SUJ2) that supports the rotating shaft, and a rapid acceleration / deceleration test was performed. The rapid acceleration / deceleration test conditions were as follows: under a 120 ° C. atmosphere, the operating conditions were set such that the load applied to the pulley attached to the tip of the rotary shaft was 1960 N, the rotation speed was 0 rpm to 18000 rpm, and the test bearing (6203) was set to 0.00. The test was performed in a state where a current of 5 A flows. Then, abnormal peeling occurred in the bearing, and the time when the vibration of the vibration detector exceeded the set value and stopped (peeling life time, h) was measured.

  As shown in Tables 1 and 2, each example in which an amine salt of an alkylaromatic sulfonic acid was blended could significantly extend the peeling occurrence life time as compared with each comparative example. This is considered to be because specific exfoliation accompanied by white texture change due to hydrogen embrittlement generated on the rolling surface could be effectively prevented.

Example 9 to Example 12, Comparative Example 11 to Comparative Example 17
Needle roller bearings (inner ring outer diameter φ24 mm, outer ring inner diameter φ32 mm, width 20 mm, rollers φ4 × 16.8 mm × 14) were lubricated with lubricating oil having the composition shown in Table 3 and subjected to a life test. The service life test is a rapid acceleration / deceleration in which the radial load is 6.76 kN, the rotation speed is 3000 rpm, 500 rpm, 3000 rpm, and 500 rpm in order, and the bearing is rotated at an ambient temperature of 100 ° C. Life time, h) was measured. The results are shown in Table 3.

  As shown in Table 3, an example in which an amine salt of an alkyl aromatic sulfonic acid was blended was compared with a comparative example in which only a water glycol hydraulic oil was used, and a comparative example in which a large amount of the same additive was blended. It was possible to extend the peeling life time. Moreover, the Example which mix | blended the amine salt of the alkyl aromatic sulfonic acid with the lubricating oil which consists of mineral oil and water was able to extend the peeling generation | occurrence | production life time significantly compared with the same lubricating oil which does not mix | blend this.

  Since the rolling bearing of the present invention can prevent specific peeling accompanied by white structure change due to hydrogen embrittlement generated on the rolling surface, it can be used for automotive electrical components such as alternators, electromagnetic clutches for car air conditioners, intermediate pulleys, electric fan motors, etc. It can be suitably used as a bearing used in rolling bearings used in auxiliary machines, rolling bearings used in motors for industrial machinery, electric vehicle driving, etc., speed increasers such as wind power generators and reduction gears for construction machines. .

1 Deep groove ball bearing (rolling bearing)
2 Inner ring 3 Outer ring 4 Rolling element 5 Cage 6 Seal member 7 Lubricant composition 8a, 8b Opening 9 Jacket 10 Stator 11 Rotating shaft 12 Winding 13 Rotor 14 Commutator 15 Brush holder 16 Brush 17 End frame 21 Increase Speed machine body 22 Input shaft 23 Output shaft 24 Housing 25 Lubricating oil 26 Planetary gear mechanism 27 Secondary gearbox 28 Carrier 29 Planetary gear 30 Ring gear 31 Sun gear 32 Intermediate output shaft 33 to 36 Gear 37 Rolling bearing

Claims (6)

A rolling bearing having a plurality of bearing members made of iron-based metal and a lubricant composition for lubricating the metal contact surface of each bearing member,
The lubricant composition is a lubricating oil or grease containing a base oil and an amine salt of an alkyl aromatic sulfonic acid and not containing an alkali metal salt or an alkaline earth metal salt of an inorganic acid,
In the case of the lubricating oil, the alkyl aromatic sulfonic acid amine salt is contained in an amount of 0.1 to 10% by weight, and in the case of the grease, the base oil, a thickener, A rolling bearing comprising 0.1 to 10 parts by weight with respect to 100 parts by weight of the total amount.   The rolling bearing according to claim 1, wherein the amine constituting the amine salt of the alkyl aromatic sulfonic acid is an amine having a plurality of amino groups.   The rolling bearing according to claim 2, wherein the amine salt of the alkyl aromatic sulfonic acid is diethylenetriamine salt or ethylenediamine salt of dinonylnaphthalenesulfonic acid.   The lubricant composition is the grease, and the base oil contains at least one oil selected from alkyl diphenyl ether oil, poly-α-olefin oil and ester oil, and the thickener of the grease is aliphatic diurea The rolling bearing according to claim 1, wherein the rolling bearing comprises at least one urea compound selected from a compound, an alicyclic diurea compound, and an aromatic diurea compound.   The rolling bearing according to claim 4, wherein the lubricant composition contains zinc dithiophosphate.   The lubricant composition is the lubricating oil, and the base oil includes at least one oil selected from mineral oil, highly refined mineral oil, and water-soluble lubricating oil. The rolling bearing according to claim 3.

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