JP2006077967A - Rotation transmission device with built-in one-way clutch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotation transmission device with a built-in one-way clutch which operates under conditions from high temperature to low temperature and is superior to a wear-resistant property on both locations of rolling contact and sliding contact and is bearable to corrosion. <P>SOLUTION: Grease composition G, which is filled into a one-way clutch 3 and rolling bearings 2 and 2 of the rotation transmission device with a built-in one-way clutch, includes base oil made from ester oil, a thickener made from di-urea compound, an antioxidant made from amine system compound, carboxylic acid, carboxylate, a rust-preventive agent made from at least one of esther and amine-based compound, an anti-flaking addition agent preventing flaking on a sliding surface of the one-way clutch and a raceway of the rolling bearing, zinc-based compound, and a wear-resistant agent made from at least one of phosphorus-based compound and sulfur-based compound. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a rotation transmission device with a built-in one-way clutch, and more particularly to a rotation transmission device with a built-in one-way clutch that operates from low to high temperatures and has excellent wear resistance.

Conventionally, a rotation transmission device with a built-in one-way clutch has been used to drive automotive auxiliary equipment such as an alternator (see Patent Document 1). A one-way clutch built-in type rotation transmission device includes a rolling bearing and a one-way clutch, and each is generally lubricated with a grease composition. Various lubricants are known for the one-way clutch built-in type rotation transmission device. For example, a grease composition based on ether oil (see, for example, Patent Document 2), and a pressure viscosity coefficient of 12 GPa ^−1. A grease composition in which a urea-based thickener is blended with the above-described ester-based or synthetic oil-based base oil (see, for example, Patent Document 3), a thickener composed of a urea compound, and a temperature at 40 ° C Grease compositions comprising a base oil having a kinematic viscosity of 60 cSt or less (see, for example, Patent Document 4) and grease compositions using silicone oil as a base oil are known (see, for example, Patent Document 5). In addition, a grease composition having a blending degree of 280 to 300 using ether oil as a base oil is enclosed in a rolling bearing, and a grease composition having a smaller blending degree (250 to 280) is enclosed in a one-way clutch. A direction clutch built-in type rotation transmission device (see, for example, Patent Document 6) is also known.
JP 2002-130433 A JP 11-82688 A JP 2000-234638 A JP 2000-253620 A Japanese Patent No. 3033306 JP 2002-130433 A

  However, since the grease composition based on ether oil described in Patent Document 2 is not suitable for use in sliding lubrication, it is particularly early when used in a one-way clutch built-in rotation transmission device for starter applications. May lose functionality. Moreover, although the grease composition having an increased pressure-viscosity coefficient described in Patent Document 3 is effective in improving the clutch lock performance, the performance in an overrun state is not sufficient. In addition, the grease composition using the low-viscosity base oil described in Patent Document 4 exhibits insufficient fretting resistance and heat resistance, but has insufficient lubrication performance during sliding. In addition, in the grease composition based on silicone oil described in Patent Document 5, silicone oil generally has a lower oil film strength than other lubricating oils, and thus there is a problem in terms of life. In addition, when different grease compositions are enclosed in the one-way clutch and the rolling bearing as in the one-way clutch built-in type rotation transmission device described in Patent Document 6, when the two grease compositions are mixed, the grease composition is softened or Curing may occur and the grease composition may deteriorate. In addition, in the device configuration in which the one-way clutch is arranged in the center and the rolling bearings are disposed at both ends, the hard grease composition leaked from the one-way clutch is pushed out to the grease composition enclosed in the rolling bearing. The amount of outflow to the outside of the device is large, which is a problem in terms of lubrication life.

Further, although the elastic force of the spring is used for clutch locking of the one-way clutch, the grease composition must not inhibit the operation of the spring even at a low temperature.
Therefore, the present invention provides a rotation transmission device with a built-in one-way clutch that encloses a grease composition that can sufficiently meet these requirements.

In order to solve the above problems, a one-way clutch built-in type rotation transmission device according to claim 1 of the present invention is an inner diameter side member, and a cylindrical shape arranged concentrically with the inner diameter side member around the inner diameter side member. A rolling bearing provided between an outer diameter side member, an outer peripheral surface of the inner diameter side member, and an inner peripheral surface of the outer diameter side member, and supports the inner diameter side member and the outer diameter side member in a relatively rotatable manner. And a rotational force that is provided between the outer peripheral surface of the inner diameter side member and the inner peripheral surface of the outer diameter side member and transmits only the rotational force that rotates the outer diameter side member relative to the inner diameter side member in a predetermined direction. In the rotation transmission device with a built-in one-way clutch provided with a one-way clutch, the rolling bearing and the one-way clutch are lubricated with a grease composition, and the grease composition has a kinematic viscosity at 40 ° C. of 20 mm. ² / s or greater 60mm ² s or less and a pour point of −45 ° C. or less of an ester oil, a diurea compound thickener, an amine compound antioxidant, a carboxylic acid, a carboxylate salt, an ester, and an amine compound A rust preventive agent comprising at least one of the above, a peeling-resistant additive for preventing the sliding surface of the one-way clutch and the raceway surface of the rolling bearing, and a zinc-based compound, a phosphorus-based compound, and a sulfur-based compound An anti-wear agent comprising at least one of the anti-oxidant and the anti-rust agent in an amount of 0.5% by mass or more and 1% by mass to 10% by mass in total. The miscibility is 250 or more and 340 or less.

The one-way clutch built-in type rotation transmission device according to claim 2 of the present invention is characterized in that, in claim 1, the diurea compound is a diurea compound represented by the following formula (1).
R ₁ —NHCO—R ₃ —NHCO—R ₂ Formula (1)
(In the formula (1), R ₁ and R ₂ are hydrocarbon groups having 6 to 18 carbon atoms, which may be the same or different, and R ₃ is an aromatic hydrocarbon group having 6 to 15 carbon atoms. is there.)
The rotation transmission device with a built-in one-way clutch according to claim 3 of the present invention is the grease composition according to claim 1 or 2, wherein the grease composition contains 1 to 10% by mass of metal dithiocarbamate as the peeling-resistant additive. It is characterized by that.

  The one-way clutch built-in type rotation transmission device of the present invention operates under conditions of low to high temperature, has excellent wear resistance at both sliding contact and rolling contact, and is resistant to corrosion.

Next, embodiments of the present invention will be described with reference to the drawings.
First, the configuration of the one-way clutch built-in type rotation transmission device of the present embodiment will be described with reference to FIG.
[Configuration of rotation transmission device with built-in one-way clutch]
1 is used in a starter, and includes a pulley (rotating member) 12 and a sleeve (rotating member) arranged concentrically with the pulley 12 on the inner diameter side of the pulley 12. ) 11, and rolling bearings 2, 2 and a one-way clutch 3 provided between the sleeve 11 and the pulley 12.

  The outer circumferential surface of the pulley 12 is formed with irregularities so that the cross section along the axial direction is corrugated, and an endless belt (V belt) (not shown) is stretched around the irregular surface. Although not shown, the endless belt is also looped over a rotation transmission member (pulley or the like) attached to the engine crankshaft, and the rotation of the pulley 12 is transmitted to the engine crankshaft via the endless belt. It has become.

In this embodiment, the sleeve 11 is externally fixed to the rotation shaft S of the starter motor. A large-diameter portion 11A having a large outer diameter is formed in an intermediate portion in the axial direction of the sleeve 11, and the one-way clutch 3 is installed here. Further, a protruding portion 11B having a larger outer diameter is formed at one axial end portion of the large diameter portion 11A of the sleeve 11.
The pair of rolling bearings 2 and 2 are fitted to both ends of the sleeve 11 in the axial direction. Each rolling bearing 2 is a deep groove ball bearing including an inner ring 21, an outer ring 22, a ball (rolling element) 23, a cage 24, and a pair of seals 25 and 25.

  The bearing internal space sealed by the pair of seals 25, 25 is filled with a grease composition G (the composition will be described later). The amount of the grease composition G enclosed is determined by subtracting the volume of the ball 23 and the cage 24 existing in the space from the volume of the bearing inner space (the volume of the space surrounded by the inner ring 21, the outer ring 22 and the seals 25, 25). About 30% by volume of the volume) is appropriate.

The one-way clutch 3 is provided adjacent to a pair of rolling bearings 2 and 2 that are fitted to both ends of the sleeve 11 in the axial direction. The configuration includes an inner ring 31 for clutch, an outer ring 32 for clutch, a plurality of rollers 33 arranged between the inner ring 31 for clutch and the outer ring 32 for clutch, and a retainer 34 for clutch that holds the roller 33, Is provided.
The clutch inner ring 31 is externally fitted to the large-diameter portion 11A of the sleeve 11, and the outer periphery of the inner ring 31 is formed with a plurality of concave ramp portions 31a that gradually become deeper in the circumferential direction at equal intervals in the circumferential direction. Has been.

The clutch outer ring 32 is fitted into the inner peripheral surface of the pulley 12, and the inner peripheral surface facing the clutch inner ring 31 is a normal cylindrical surface. A pair of flanges 32a and 32a projecting toward the clutch inner ring 31 are formed at both ends in the axial direction.
A clutch internal space is formed between the clutch inner ring 31 and the clutch outer ring 32 so as to be surrounded by the flanges 32a, 32a, and the plurality of rollers 33 held by the clutch retainer 34 are respectively circumferentially arranged. It is arranged to be slidable in the direction.

  The clutch retainer 34 includes a column portion (not shown) having a spring, and a locking projection 34a formed at one end portion in the axial direction of the column portion. The spring biases the roller 33 when the clutch is locked. The locking protrusion 34 a has a shape protruding toward the sleeve 11, is disposed so as to be sandwiched between the protrusion 11 B of the sleeve 11 and the inner ring 31 for clutch, and extends in the axial direction of the clutch retainer 34. Suppresses movement.

  The clutch internal space is filled with the same grease composition G as that enclosed in the rolling bearings 2 and 2. The amount of the grease composition G enclosed is determined by subtracting the volume of the inner space of the clutch (the volume of the space surrounded by the inner ring 31 for clutch and the outer ring 32 for clutch from the volume of the roller 33 and the retainer 34 for clutch). About 70% by volume of the volume).

Next, the operation of the one-way clutch built-in rotation transmission device having the above-described configuration will be described.
When the rotation shaft S is rotated by driving the starter motor, the clutch inner ring 31 fitted on the sleeve 11 is also rotated, and the roller 33 is also moved in a direction in which the recess of the ramp portion 31a of the clutch inner ring 31 becomes shallower. When the roller 33 is also pushed out by the spring of the clutch retainer 34, the roller 33 bites between the ramp portion 31 a of the clutch inner ring 31 and the inner peripheral surface 32 b of the clutch outer ring 32, and the clutch inner ring 31 and the clutch The outer ring 32 is connected (clutch locked state). Thereby, a rotational force is transmitted from the sleeve 11 to the pulley 12, and the rotation of the starter motor is transmitted to the crankshaft via the endless belt.

  When the rotation speed of the crankshaft increases and the rotation speed of the pulley 12 due to the travel of the endless belt becomes larger than the rotation speed of the sleeve 11 due to the rotation of the rotation shaft S of the starter motor, the roller 33 also moves in the opposite direction. Move to. In other words, the ramp portion 31a moves from the biting position while sliding in a direction in which the recess of the ramp portion 31a becomes deep, the locked state is released, and the connection between the clutch inner ring 31 and the clutch outer ring 32 is disconnected (overrun state). In this state, supported by the rolling bearings 2 and 2, the pulley 12 rotates relative to the sleeve 11, and the rotation of the crankshaft is not transmitted to the rotating shaft S of the starter motor.

  The one-way clutch built-in type rotation transmission device to which the present invention is applied is not limited to the one having the above configuration. For example, the outer ring 32 for the clutch may be a cylindrical one having no flange 32a, a ramp portion may be provided on the inner peripheral surface of the outer ring 32 for the clutch, or the outer ring 32 for the clutch may be omitted, and the pulley 12 It is also possible to directly use the inner peripheral surface of this as the sliding surface of the one-way clutch. Similarly, the outer peripheral surface of the sleeve 11 may be directly used as the sliding surface of the roller 33 without providing the inner ring 31 for clutch.

  Further, the pair of rolling bearings 2 and 2 are not limited to ball bearings, and even when a roller bearing is used, and even when both a roller bearing and a ball bearing are used, the same effect can be obtained. can get. Further, in this embodiment, the seals 25 and 25 are provided at both ends of the rolling bearings 2 and 2 to seal the bearing internal space, but the one-way clutch 3 side of the both ends of the rolling bearings 2 and 2 is disposed. It is not necessary to install the seal 25 at the end.

  Further, the one-way clutch built-in type rotation transmission device of the present invention is not limited to the one for starter use as described above, and is used for driving an automobile auxiliary machine such as an alternator and a car air conditioner. Also good. In this case, the rotation transmission device with a built-in one-way clutch is attached to a rotating shaft of an auxiliary machine such as an alternator, and an endless belt connected to a driving shaft such as an engine crankshaft is stretched around the outer periphery. As a result, when the rotational speed of the drive shaft increases, the driving force is transmitted to the rotational shaft of the auxiliary equipment for the automobile, but when the rotational speed of the drive shaft decreases, the driving force is not transmitted. Thus, for example, when used in an alternator, it is possible to improve the power generation efficiency and prevent the endless belt from being shortened.

  The one-way clutch built-in type rotation transmission device of the present invention may be used for an accessory driving device that drives an accessory when the engine is idling. In this case, the one-way built-in rotation transmission device is mounted on the crankshaft of the engine and the drive shaft of the accessory drive device. As a result, when one of the engine and the auxiliary drive device is in an operating state and the other is in a stopped state, the rotational force can be freely transmitted from the device in the operating state to the pulley, and the stop is stopped. Prevent the drive shaft of the device in the state from rotating.

[Grease composition]
In the present invention, the grease composition includes a base oil composed of an ester oil, a thickener composed of a diurea compound, an antioxidant composed of an amine compound, a carboxylic acid, a carboxylate salt, an ester, and an amine compound. A rust preventive agent comprising at least one, a peeling resistance additive, and an antiwear agent comprising at least one of a zinc compound, a phosphorus compound and a sulfur compound are contained.
Ester oil (base oil) is more polar than other lubricating oils. For this reason, by using ester oil as the base oil, the one-way clutch built-in rotation transmission device has excellent impact resistance during sliding friction.

  Although the kind of ester oil is not specifically limited, Diester oil, polyol ester oil, aromatic ester oil, etc. can be used conveniently. Specific examples of the diesel oil include dioctyl adipate (DOA), diisobutyl adipate (DIBA), dibutyl adipate (DBA), dioctyl azelate (DOZ), dibutyl sebacate (DBS), dioctyl sebacate (DOS), and the like. be able to. Examples of polyol ester oils include pentaerythritol ester oils, dipentaerythritol ester oils, tripentaerythritol oils, neopentyl diol ester oils, and trimethylol bropan ester oils having an alkyl chain having 4 to 18 carbon atoms. be able to. Examples of the aromatic ester oil include polyol ester oil, trioctyl trimellitate (TOTM), tridecyl trimellitate, tetraoctyl pyromellitate and the like. These may be used alone or in appropriate combination.

The ester oil has a kinematic viscosity at 40 ° C. of ²⁰ to 60 mm ² / s and a pour point of −45 ° C. or lower. When the kinematic viscosity is less than 20 mm ² / s, the grease composition is inferior in heat resistance, and when it exceeds 60 mm ² / s, heat generation during sliding increases. In addition, since the automobile must withstand use (engine start) near -40 ° C, the pour point of the base oil needs to be -45 ° C or less.

As a thickener, a diurea compound is used. Diurea compounds are excellent in heat resistance. In particular, it is preferable to use a diurea compound represented by the following formula (1).
R ₁ —NHCO—R ₃ —NHCO—R ₂ Formula (1)
In the formula (1), R ₁ and R ₂ are hydrocarbon groups having 6 to 18 carbon atoms, which may be the same or different, and R ₃ is an aromatic hydrocarbon group having 6 to 18 carbon atoms. Among these, a diurea compound in which R ₁ and R ₂ are cyclohexyl groups, or a diurea compound in which a cyclohexyl group and an aliphatic group are mixed is preferable.

Incidentally, diurea compounds obtained by introducing aromatic groups in R _1, R ₂ tends to cure by heating, it may not be suitable for sliding lubrication at high temperatures. Further, the blending amount of the thickener is not limited as long as the grease composition is formed with the base oil, but 10 to 20% by mass of the entire grease composition is appropriate.
Examples of the amine compound that can be used as an antioxidant include any aromatic amine compound that is used as an antioxidant for lubricating oils and resins. Thus, by adding an antioxidant, the oxidative deterioration of the base oil during high temperature use is suppressed and the life is prolonged.
Among the aromatic amine compounds, α-naphthylamines and diphenylamines are preferable.
As α-naphthylamines, those represented by the following formula (2) are preferable.

In the above formula (2), R ₄ is a hydrogen atom or a group represented by the following formula (3), preferably a group represented by the following formula (3).

In the above formula (3), R ₅ is a hydrogen atom or a linear or branched alkyl group having 1 to 16 carbon atoms.
Examples of the alkyl group represented by R ₅ include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, and a tridecyl group. , Tetradecyl group, pentadecyl group, hexadecyl group and the like (these alkyl groups may be linear or branched), among which a branched alkyl group having 8 to 16 carbon atoms is preferable.
As diphenylamines, those represented by the following formula (4) are preferable.

R ₆ and R ₇ in the above formula (4) are a hydrogen atom or an alkyl group having 1 to 16 carbon atoms, preferably an alkyl group having 1 to 16 carbon atoms. R ₆ and R ₇ may be the same or different. When one or both of R ₆ and R ₇ are hydrogen atoms, they may settle as sludge due to their own oxidation.
Examples of the alkyl group represented by R ₆ and R ₇ include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, A tridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl group, etc. (these alkyl groups may be linear or branched) are mentioned, and among them, a branched alkyl group having 3 to 16 carbon atoms is preferable.

In addition to the amine compounds represented by the formulas (2) and (4), Nn-butyl-p-aminophenol, 4,4′-tetramethyldiaminodiphenylmethane, N, N-disalicylidene-1, Amine-based antioxidants such as 2-propylenediamine can be used.
The amine compounds as the antioxidant can be used alone or as a mixture of a plurality of them, but the amount added is 1% by mass or more of the entire grease composition. If it is less than this, a sufficient effect cannot be obtained.

  Examples of carboxylic acid and carboxylate that can be used as a rust preventive include stearic acid, alkyl succinic acid, alkenyl succinic acid, alkyl succinic acid or alkenyl succinic acid derivative, naphthenic acid, abietic acid, lanolin fatty acid, and And metal salts thereof (calcium, barium, magnesium, aluminum, zinc, lead, etc.). Among these, alkenyl succinic acid and zinc naphthenate are particularly preferably used.

Examples of ester compounds that can be used as rust preventives include carboxylic acid partial esters of polyhydric alcohols (sorbitan monooleate, sorbitan trioleate, pentaerythritol monooleate, succinic acid half ester, etc.). In particular, sorbitan monooleate and succinic acid half ester are preferred.
Examples of amine compounds that can be used as rust inhibitors include amine derivatives such as alkoxyphenylamines and partial amides of dibasic carboxylic acids.

Thus, by adding a rust preventive agent, it is possible to effectively prevent the occurrence of rust even in the one-way clutch built-in type rotation transmission device that is arranged in the engine room and easily contacts with rainwater or the like. it can.
The total amount of addition of the antioxidant and the rust inhibitor is in the range of 1% by mass to 10% by mass of the entire grease composition. If the total addition amount of the antioxidant and the rust preventive exceeds 10% by mass, the antioxidant and rust preventive effects are saturated, so there is no meaning to add more.

  In the present invention, the anti-peeling additive is an additive that has both an action against extreme pressure and an anti-peeling action on the sliding surface of the one-way clutch and the raceway surface of the rolling bearing. For example, metal dithiocarbamate (ZnDTC, etc.) Can be used. The amount of metal dithiocarbamate added is 1 to 10% by mass. Moreover, since it is a use with much sliding friction, it is good to add a little.

As an antiwear agent added to the grease composition, at least one selected from zinc compounds, phosphorus compounds and sulfur compounds is used.
The zinc compound is preferably zinc dialkyldithiophosphate.
As the phosphorus compound and sulfur compound, known antiwear agents can be used. For example, sulfurized fats and oils, sulfurized olefins, tricresyl phosphate, thiophosphate, and thiophosphite can be used. In particular, thiophosphate can be preferably used.

These can be used alone or in combination. The amount of these antiwear agents is 0.1 to 5% by mass. Preferably, 0.3-2 mass% is mix | blended. If it is less than 0.1% by mass, it is difficult to obtain the desired effect sufficiently. On the other hand, if it exceeds 5% by mass, the anti-wear effect is saturated and the thermal stability is inferior, which is not practical.
In addition, extreme pressure agents (phosphorus, zinc dithiophosphate, organic molybdenum, etc.), oiliness improvers (fatty acids, animal and vegetable oils, etc.), metal deactivators (benzotriazole, etc.), etc. If there is, it can be added appropriately. In particular, it is preferable to add organic molybdenum as an extreme pressure agent because frictional wear during sliding is further reduced. As the organic molybdenum, molybdenum dithiophosphate, molybdenum dithiocarbamate, an amine complex of molybdenum, and the like are suitable, and the content thereof is preferably 1 to 10% by mass of the total amount of the grease composition.

  Further, the penetration of the grease composition is in the range of 250 to 340. When the penetration is less than 250, it is difficult for the grease composition to spread mainly to the sliding contact portion of the one-way clutch. The one-way clutch lock also uses the force of the spring, but there is a problem that the movement of the spring is worsened. On the other hand, when the blending degree exceeds 340, there arises a problem that the grease composition tends to flow out due to vibration during traveling.

  The grease composition contains each of the above components, but there is no limitation on the production method thereof, and it can be prepared in the same manner as a grease composition using a conventional urea compound as a thickener. It is obtained by reacting raw materials of diurea compounds (amines and diisocyanate) in a base oil. The production conditions such as the heating temperature, stirring, and mixing time at that time are appropriately set depending on the base oil and diurea compound raw materials, additives, and the like to be used. Moreover, after adding an additive, it is necessary to stir well and to disperse | distribute uniformly, but heating in that case is also effective.

Hereinafter, a reciprocating friction test, a low temperature torque test, an evaporation loss test, a peel resistance test, and a rust prevention test are performed in order to confirm the effects of the one-way clutch built-in type rotation transmission device of the present invention and the grease composition used therefor. I went and explained. In addition, this invention is not restrict | limited by the following Example.
[Grease composition]
A diurea compound is synthesized by reacting amines and diisocyanate (MDI: 4,4'-diphenylmethane diisocyanate) in the base oil, dispersed in the base oil, and after adding a predetermined amount of additives, a three-stage roll mill The grease compositions of Examples and Comparative Examples shown in Table 1 and Table 2 were prepared and used for each test.

  In addition, as base oil, polyol ester (PE, Kao Corporation, Kaorubu series), alkyl diphenyl ether (ADE, Matsumura Oil Research Laboratory, LB series), poly-α-olefin (PAO, Exxon Mobil, Either SHF series) or mineral oil was used. As an antiwear agent, ZnDTP (manufactured by Lubrizol, Lubrizol 1195) was used.

[Reciprocating friction test]
The grease composition was subjected to a reciprocating friction test at high speed to evaluate the performance during sliding.
FIG. 2 shows the reciprocating friction test. First, a grease composition as a specimen is applied to a test flat plate 94 (manufactured by SUJ2, HRC 60-64) 94 placed on the test table 91 in a thickness of about 0.05 mm, and heated by a heater 92 at 140 ° C. for 2 hours. And left to reach room temperature. Thereafter, a test ball 95 having a diameter of 10 mm is pressed against the test flat plate 94 coated with the grease composition, and the test ball 95 is reciprocated by a cam 97 for 30 minutes (frequency 10 Hz, amplitude 2 mm) while applying a vertical load of 96 N. The test was conducted. After the test, the wear scar diameter (mm) of the test ball was measured. 2 is a thermocouple, and detects the heating temperature by the heater 92. Reference numeral 96 denotes a load cell which observes the reciprocating motion of the cam 97.

[Low temperature torque test]
The low temperature property of the grease composition was evaluated by performing a low temperature torque test specified in JIS K2220 5.14. The test results are shown in Tables 1 and 2 as ◎ when the stopping force is less than 15N, ◯ when the stopping force is 15N or more and less than 25N, and x when the stopping force is 25N or more.
[Evaporation loss test]
15 mg of the grease composition was sampled, and the heat resistance of the grease composition was evaluated by measuring the weight loss after 160 hours at 160 ° C. using a thermogravimetric apparatus (TG). The test results are ◎ when the weight loss is less than 4% of the grease composition collected before the test, and similarly, when the weight loss is 4% or more and less than 6%, ○, when the weight loss is 6% or more. The results are shown in Tables 1 and 2 with x.

[About peeling test]
In the peel resistance test, a rotation transmission device with a built-in one-way clutch similar to that shown in FIG. 1 is fitted on the rotation shaft S of the alternator, and its pulley 12 is connected to the actual engine through a belt to It was done by sudden acceleration / deceleration.
A single row deep groove ball bearing (inner diameter: 17 mm, outer diameter: 47 mm, width: 14 mm) was used as the rolling bearing 2, and 2.5 g of the grease compositions of Examples and Comparative Examples were sealed in the rolling bearing 2. Test, the pulley load (load received from the belt) and 1560N, was 500 hours continuous rotation by the engine rotational speed 1000～6000Min ^-1 (bearing rotational speed 2400~13300min ^-1). The vibration generated in the one-way clutch built-in type rotation transmission device was measured during the test, and the test was terminated when the vibration value became larger than the specified value or when the specified 500 hours were reached. The test was conducted on ten one-way clutch built-in type rotation transmission devices. After the test, the presence or absence of separation of the raceway surface of the rolling bearing 2 was confirmed, and the ratio of the one-way clutch built-in type rotation transmission device in which the separation occurred was used as a test result.

[About rust prevention test]
After 2.7 g of the grease composition to be tested was sealed in a single row deep groove ball bearing (inner diameter 17 mm, outer diameter 47 mm, width 14 mm), 0.3 cc of 0.1% sodium chloride aqueous solution was injected into the bearing and contactless sealing was performed. Rotation was carried out after fitting. Thereafter, the bearing was left in an environment of 60 ° C. and a relative humidity of 70% for 3 days, and the state of the bearing inner ring raceway surface was observed. The test results were determined to be unacceptable when the occurrence of rust was confirmed visually, and otherwise acceptable.

As described above, as shown in each test result, in Examples 1 to 5 to which the peeling resistance additive was added, no peeling occurred in the peeling resistance test. On the other hand, in Comparative Examples 1 and 2 to which no release additive was added, peeling occurred at a high ratio of 4/10 to 5/10, and it was confirmed that the release additive exhibits an excellent peeling effect. It was.
Moreover, in Examples 1-5, compared with Comparative Examples 1-5, the wear scar diameter was comparatively small. For this reason, when the grease composition of Examples 1-5 was used, it was confirmed that it is excellent in abrasion resistance also at the time of a sliding contact.
Furthermore, from the results of the low-temperature torque test, the evaporation loss test, and the rust prevention test, it was confirmed that the grease compositions of Examples 1 to 5 were excellent in fluidity, heat resistance, and rust prevention at low temperatures.

It is a figure which shows the structure of the rotation transmission apparatus with a built-in one-way clutch of this embodiment. It is a figure which shows the mode of a reciprocating friction test.

Explanation of symbols

11 Sleeve 11A Large diameter portion 11B Protrusion portion 12 Pulley 2 Rolling bearing 21 Inner ring 22 Outer ring 23 Ball 24 Cage 25 Seal 3 One-way clutch 31 Clutch inner ring 31a Ramp portion 32 Clutch outer ring 32a 鍔 32b Inner peripheral surface 33 Roller 34 Clutch Cage 34a Locking projection G Grease composition S Rotating shaft

Claims (3)

An inner diameter side member, a cylindrical outer diameter side member arranged concentrically with the inner diameter side member around the inner diameter side member, an outer peripheral surface of the inner diameter side member, and an inner peripheral surface of the outer diameter side member Provided between the rolling bearing that supports the inner diameter side member and the outer diameter side member in a relatively rotatable manner, and the outer peripheral surface of the inner diameter side member and the inner peripheral surface of the outer diameter side member. A one-way clutch built-in type rotation transmission device comprising: a one-way clutch that transmits only a rotational force for rotating the outer diameter side member relative to the inner diameter side member in a predetermined direction;
The rolling bearing and the one-way clutch are lubricated with a grease composition;
The grease composition is
A base oil composed of an ester oil having a kinematic viscosity at 40 ° C. of 20 mm ² / s to 60 mm ² / s and a pour point of −45 ° C., a thickener composed of a diurea compound, and an antioxidant composed of an amine compound. And a rust preventive comprising at least one of carboxylic acid, carboxylate, ester and amine compound, and a delamination-resistant additive for preventing separation of the sliding surface of the one-way clutch and the raceway surface of the rolling bearing And an antiwear agent comprising at least one of a zinc compound, a phosphorus compound, and a sulfur compound, and the contents of the antioxidant and the rust inhibitor are each 0.5. A one-way clutch built-in type rotation transmission device having a mass percentage of not less than 1% and not less than 1% by mass and not more than 10% by mass, and having a blending consistency of not less than 250 and not more than 340. The one-way clutch built-in rotation transmission device according to claim 1, wherein the diurea compound is a diurea compound represented by the following formula (1).
R ₁ —NHCO—R ₃ —NHCO—R ₂ Formula (1)
(In the formula (1), R ₁ and R ₂ are hydrocarbon groups having 6 to 18 carbon atoms, which may be the same or different, and R ₃ is an aromatic hydrocarbon group having 6 to 15 carbon atoms. is there.)   3. The one-way clutch built-in rotation transmission device according to claim 1, wherein the grease composition contains 1% by mass or more and 10% by mass or less of metal dithiocarbamate as the peeling resistance additive.

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