JP2011112185A - Rolling bearing for automobile electrical equipment and auxiliary machinery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing for an automobile electrical equipment and auxiliary machinery, effectively preventing separation on a rolling contact surface caused by hydrogen brittleness and used for a long period of time, under the conditions of use of the rolling bearing used for the automobile electrical equipment and auxiliary machinery. <P>SOLUTION: This rolling bearing 1 for the automobile electrical equipment and auxiliary machinery rotatably supports a rotating shaft rotatively driven by the output of an engine in a stationary member. The rolling bearing 1 for the automobile electrical equipment and auxiliary machinery includes an inner ring 2, an outer ring 3, a plurality of rolling elements 4 interposed between the inner and outer rings, and a retainer 5 retaining the rolling elements 4, as metallic bearing members. At least one selected from the metallic bearing members is a member with the sliding surface or rolling contact surface of the member coated with a plant-derived polyhydric alcohol compound. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rolling bearing used for an automotive electrical component such as an alternator, an electromagnetic clutch for a car air conditioner, a fan coupling device, an intermediate pulley, and an electric fan motor, and an auxiliary machine.

  In recent years, along with demands for miniaturization, weight reduction and quietness improvement of automobiles, miniaturization, weight reduction and sealing of engine compartments have been attempted for the electrical parts and auxiliary parts. The demand for high output and high efficiency is increasing in the performance of the engine itself, and in the electrical equipment and auxiliary equipment in the engine room, a method of compensating for the decrease in output caused by downsizing by rotating at high speed is adopted. Yes. Hereinafter, outlines of a rolling bearing for a fan coupling device, a rolling bearing for an alternator for an automobile, and a rolling bearing for an idler pulley will be described as examples of the rolling bearing for an electric vehicle / auxiliary machine.

  A fan coupling device for automobiles has a housing in which viscous fluid is sealed inside and a fan for blowing air on the outer peripheral surface is connected to a rotor directly connected to the engine via a bearing, and increases or decreases in response to the ambient temperature. It is a device that performs optimum ventilation corresponding to the engine temperature by controlling the amount of drive torque transmitted from the engine and the rotational speed of the fan using the shearing resistance of the viscous fluid. For this reason, the rolling bearings for fan coupling devices have a rotational speed of 10000 rpm at a high temperature of 180 ° C or higher during high-speed operation in summer, in addition to uneven rotation that varies from 1000 rpm to 10000 rpm as the engine temperature fluctuates. Heat resistance, grease sealability, and durability that can withstand extremely harsh environments such as high-speed rotation at rpm or higher are required.

  The alternator for automobiles has a function of generating power by receiving rotation of an engine with a belt, supplying electric power to an electric load of the vehicle, and charging a battery. For this reason, rolling bearings for alternators are required to have heat resistance, grease sealability, and durability that can withstand extremely harsh environments such as high-speed rotations of 10,000 rpm or higher at high temperatures of 180 ° C or higher.

  The idler pulley for automobiles is used as a belt tensioner for a drive belt that transmits engine rotation to the auxiliary equipment of the automobile, and is used to apply tension as a tensioner to the belt when the center distance is fixed. It functions in combination with a pulley function and an idler function that reduces the engine compartment volume by changing the running direction of the belt or avoiding obstacles. For this reason, idler pulley rolling bearings are required to have heat resistance, grease sealability, and durability that can withstand extremely harsh environments such as high-speed rotation of 10,000 rpm or higher at a high temperature of 180 ° C or higher.

  Grease is mainly used for lubrication of these rolling bearings. However, due to severe conditions of use such as rapid acceleration / deceleration, high temperature, and high speed rotation, specific peeling accompanied with a change in white structure occurs at an early stage on the rolling surface of the rolling bearing. This specific exfoliation is a destructive phenomenon that occurs from a relatively shallow part of the surface of the rolling surface, unlike the internal peeling caused by normal metal fatigue. It is considered brittle.

  As a method for preventing such a peculiar exfoliation phenomenon accompanied with a white tissue change that occurs at an early stage, for example, a method of adding a passivating agent to grease (see Patent Document 1), a method of adding bismuth dithiocarbamate (Patent) Document 2) is known.

JP-A-3-210394 JP-A-2005-42102

  However, as the usage conditions of rolling bearings used in automotive electrical equipment and accessories in recent years have become severe, the method of adding the passivating agent of Patent Document 1 and bismuth dithiocarbamate of Patent Document 2 is a measure to prevent the peeling phenomenon. It is becoming insufficient.

  The present invention has been made to cope with such problems, and can effectively prevent separation on the rolling surface due to hydrogen embrittlement under the use conditions of the rolling bearing used in automobile electrical equipment and auxiliary equipment, The purpose is to provide rolling bearings for automobile electrical equipment and auxiliary equipment that can be used for a long time.

  A rolling bearing for automobile electrical equipment / auxiliary machinery according to the present invention is a rolling bearing for automotive electrical equipment / auxiliary machinery that rotatably supports a rotating shaft that is driven to rotate by engine output on a stationary member, and the rolling bearing for the automotive electrical equipment / auxiliary machinery is provided. The rolling bearing includes, as a metal bearing member, an inner ring, an outer ring, a plurality of rolling elements interposed between the inner and outer rings, and a cage that holds the rolling element. At least one selected is a member in which the sliding surface or rolling surface of the member is coated with a plant-derived polyhydric alcohol compound. In particular, the film-treated member is at least one selected from the inner ring and the outer ring.

  The member subjected to the coating treatment has an iron oxide coating on the sliding surface or rolling surface of the member. The coating treatment is a treatment of immersing a metal bearing member to be coated in a treatment liquid in which the plant-derived polyhydric alcohol compound is dispersed or dissolved in water and / or an organic solvent. And

  The plant-derived polyhydric alcohol compound is curcumin or a derivative thereof. The plant-derived polyhydric alcohol compound is quercetin or a derivative thereof.

  The plant-derived polyhydric alcohol compound is chlorogenic acid or a derivative thereof. The plant-derived polyhydric alcohol compound is caffeic acid or a derivative thereof. The plant-derived polyhydric alcohol compound is quinic acid or a derivative thereof.

  The plant-derived polyhydric alcohol compound is gallic acid or a derivative thereof. The plant-derived polyhydric alcohol compound is ellagic acid or a derivative thereof.

  The rolling bearing for automotive electrical equipment / auxiliary machine according to the present invention is made of a plant-derived polyhydric alcohol compound on the sliding surface or rolling surface of at least one member selected from metal bearing members constituting the bearing. Since the coating treatment is performed, specific peeling accompanied with white structure change occurring on the rolling surface can be effectively prevented, and the bearing life is excellent. For this reason, it can be suitably used as a rolling bearing for automotive electrical parts such as alternators, car air conditioner electromagnetic clutches, fan coupling devices, intermediate pulleys, and electric fan motors, and auxiliary machines.

It is sectional drawing of the deep groove ball bearing which shows one Example of the rolling bearing for motor vehicle electrical equipment and auxiliary machines of this invention. It is sectional drawing which shows the fan coupling apparatus using the rolling bearing for motor vehicle electrical equipment and auxiliary machines of this invention. It is sectional drawing which shows the alternator using the rolling bearing for motor vehicle electrical equipment and auxiliary machines of this invention. It is sectional drawing which shows the idler pulley using the rolling bearing for motor vehicle electrical equipment and auxiliary machines of this invention.

  A rolling acceleration bearing for automotive electrical equipment / auxiliary machinery whose bearing member surface was treated with a plant-derived polyhydric alcohol compound was subjected to a rapid acceleration / deceleration test, and it was found that the bearing life could be extended. This is because an iron oxide film is formed on the surface of a metal (bearing steel) bearing member due to the action of the polyhydric alcohol compound derived from the plant, and generation of hydrogen due to decomposition of the grease composition is suppressed. This is thought to be due to the prevention of peculiar delamination caused by hydrogen embrittlement on the surface. The present invention is based on this finding.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS A rolling bearing for automobile electrical equipment and auxiliary equipment according to the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a deep groove ball bearing which is an embodiment of a rolling bearing for automobile electrical equipment and auxiliary equipment according to the present invention. As shown in FIG. 1, a rolling bearing 1 is interposed between an inner ring 2 having a rolling surface 2a on an outer peripheral surface, an outer ring 3 having a rolling surface 3a on an inner peripheral surface, and the both rolling surfaces 2a, 3a. It comprises a plurality of rolling elements 4 and a cage 5 that holds the rolling elements 4. Seal members 6 fixed to the outer ring 3 and the like are provided in the axial end openings 8 a and 8 b of the inner ring 2 and the outer ring 3, respectively, and seal the grease 7 sealed around the rolling elements 4. The inner ring 2, the outer ring 3, the rolling element 4, or the cage 5 is a metal bearing member, and is derived from a plant described later on the sliding surface or rolling surface of at least one member selected from the metal bearing member. A coating treatment is performed with a polyhydric alcohol compound.

  Another embodiment of a rolling bearing for automobile electrical equipment / auxiliary machinery according to the present invention is shown in FIGS. 2 (a) and 2 (b). 2A and 2B are cross-sectional views of the structure of the fan coupling device. The fan coupling device includes an oil chamber 11 in which a viscous fluid such as silicone oil is filled in a case 10 that supports a cooling fan 9 and a stirring chamber 12 in which a drive disk 18 is incorporated. A port 14 is formed in the partition plate 13 provided therebetween, and an end of a spring 15 that opens and closes the port 14 is fixed to the partition plate 13. A bimetal 16 is attached to the front surface of the case 10, and a piston 17 of a spring 15 is provided on the bimetal 16. The bimetal 16 becomes flat when the temperature of the air that has passed through the radiator is below a set temperature, for example, 60 ° C., the piston 17 presses the spring 15, and the spring 15 closes the port 14. When the air temperature exceeds the set temperature, the bimetal 16 is bent outward as shown in FIG. 2B, the piston 17 releases the pressure of the spring 15, and the spring 15 is elastically deformed. Port 14 is opened.

  When the temperature of the air that has passed through the radiator is lower than the set temperature of the bimetal 16 in the operating state of the fan coupling device having the above configuration, the port 14 is closed by the spring 15 as shown in FIG. Therefore, the viscous fluid in the oil chamber 11 does not flow into the stirring chamber 12, and the viscous fluid in the stirring chamber 12 enters the oil chamber 11 from the circulation hole 19 provided in the partition plate 13 by the rotation of the drive disk 18. Sent. For this reason, the amount of the viscous fluid in the stirring chamber 12 becomes small, and the shear resistance due to the rotation of the drive disk 18 becomes small. Therefore, the transmission torque to the case 10 is reduced and the cooling bearing supported by the rolling bearing 1 is used. The fan 9 rotates at a low speed. When the temperature of the air that has passed through the radiator exceeds the set temperature of the bimetal 16, the bimetal 16 is bent outward as shown in FIG. 2B, and the piston 17 releases the pressure of the spring 15. At this time, since the spring 15 is elastically deformed in a direction away from the partition plate 13, the port 14 is opened, and the viscous fluid in the oil chamber 11 flows from the port 14 into the stirring chamber 12. For this reason, the shear resistance of the viscous fluid due to the rotation of the drive disk 18 increases, the rotational torque to the case 10 increases, and the cooling fan 9 supported by the rolling bearing 1 rotates at high speed.

  As described above, in the fan coupling device, the rotational speed of the cooling fan 9 changes according to the temperature change, so that warming up is accelerated and overcooling of the cooling water is prevented to effectively cool the engine. Can do. The cooling fan 9 is equivalent to being disconnected from the drive shaft 20 when the engine temperature is low, and is equivalent to being connected to the drive shaft 20 when the engine temperature is high. As described above, the rolling bearing 1 is used in a wide temperature range from a low temperature to a high temperature, and in a rapid acceleration / deceleration condition in which the number of rotations greatly fluctuates with a change in temperature. Here, the inner ring, the outer ring, the rolling element, or the cage constituting the rolling bearing 1 is a metal bearing member, and on the sliding surface or rolling surface of at least one member selected from the metal bearing member, A coating treatment is performed with a plant-derived polyhydric alcohol compound described below.

  A rolling bearing for automobile electrical equipment and auxiliary equipment used in an alternator as another embodiment of the rolling bearing for automobile electrical equipment and auxiliary equipment of the present invention will be described with reference to FIG. FIG. 3 is a sectional view of the structure of the alternator. In the alternator, a pair of frames 21a and 21b forming a housing which is a stationary member, a rotor rotating shaft 23 having a rotor 22 mounted thereon is rotatably supported by a pair of rolling bearings 1 and 1. A rotor coil 24 is attached to the rotor 22, and a three-turn stator coil 26 is attached to the stator 25 disposed on the outer periphery of the rotor 22 at a phase of 120 °. The rotor rotating shaft 23 is rotationally driven with a rotational torque transmitted by a belt (not shown) to a pulley 27 attached to the tip thereof. The pulley 27 is attached to the rotor rotating shaft 23 in a cantilever state, and vibration is also generated as the rotor rotating shaft 23 rotates at high speed. Therefore, the rolling bearing 1 that supports the pulley 27 side in particular receives a severe load. . Here, the inner ring, the outer ring, the rolling element, or the cage constituting the rolling bearing 1 is a metal bearing member, and on the sliding surface or rolling surface of at least one member selected from the metal bearing member, A coating treatment is performed with a plant-derived polyhydric alcohol compound described below.

  An example of an idler pulley used as a belt tensioner for an automobile accessory drive belt is shown in FIG. FIG. 4 is a sectional view of the structure of the idler pulley. The pulley includes a pulley body 28 made of a steel plate press and a single row deep groove ball bearing 1 fitted to the inner diameter of the pulley body 28. The pulley main body 28 includes an inner diameter cylindrical portion 28a, a flange portion 28b extending from one end of the inner diameter cylindrical portion 28a to the outer diameter side, an outer diameter cylindrical portion 28c extending in the axial direction from the flange portion 28b, and an inner diameter cylindrical portion 28a. This is an annulus composed of a flange portion 28d extending from the other end to the inner diameter side. The outer ring 3 of the deep groove ball bearing 1 shown in FIG. 1 is fitted to the inner diameter of the inner diameter cylindrical portion 28a, and the outer peripheral diameter of the outer diameter cylindrical portion 28c is provided with a pulley peripheral surface 28e that contacts the belt driven by the engine. It has been. By bringing the pulley peripheral surface 28e into contact with the belt, the pulley functions as an idler. Here, the inner ring, the outer ring, the rolling element, or the cage constituting the rolling bearing 1 is a metal bearing member, and on the sliding surface or rolling surface of at least one member selected from the metal bearing member, A coating treatment is performed with a plant-derived polyhydric alcohol compound described below.

  Details of the components of the rolling bearing 1 for automobile electrical equipment and auxiliary equipment of the present invention will be described with reference to FIG. Bearing members such as the inner ring 2, the outer ring 3, the rolling elements 4, and the cage 5 are made of a well-known bearing metal material. In the present invention, at least one of the metal bearing members needs to be made of a metal material that can be coated with a plant-derived polyhydric alcohol compound. Specific examples of the bearing ring material include bearing steel (high carbon chromium bearing steel JIS G 4805), case-hardened steel (JIS G4104, etc.), high-speed steel (AMS 6490), stainless steel (JIS G4303), induction-hardened steel. Steel entering (JIS G4051 etc.) etc. are mentioned. Examples of cage materials include cold rolled steel plates for punching cages (JIS G 3141, etc.), carbon steel for machined cages (JIS G4051), high strength brass castings for machined cages (JIS H 5102, etc.), and the like. It is done. Other bearing alloys can also be employed.

  The seal member 6 may be made of a metal or a rubber molded body alone, or may be a composite of a rubber molded body and a metal plate, a plastic plate, a ceramic plate, or the like. From the viewpoint of durability and ease of fixing, a composite of a rubber molded body and a metal plate is preferable.

  A rolling bearing for automobile electrical equipment / auxiliary machinery according to the present invention is a rolling bearing for automotive electrical equipment / auxiliary machinery in which a lubricant such as lubricating oil or grease 7 is applied or filled inside the bearing. Further, the bearing type is not particularly limited to a type such as a radial ball bearing or a thrust ball bearing. The lubricant is not particularly limited as long as it is a lubricant generally used for bearings.

  In the rolling bearing for automobile electrical equipment / auxiliary machinery of the present invention, the coating treatment applied to the sliding surface or rolling surface of the metal bearing member is performed by applying an iron oxide coating on the surface by the action of the plant-derived polyhydric alcohol compound. Any coating process may be used as long as it is formed, and the coating method is not particularly limited. As a coating treatment method, for example, a metal bearing member to be coated is immersed in a treatment liquid in which a plant-derived polyhydric alcohol compound is dispersed or dissolved in water and / or an organic solvent, and iron oxide is formed on the member surface. A method of forming a film can be employed. In this method, it is preferable to carry out heating while accelerating the film formation.

  Further, by applying a treatment liquid in which a plant-derived polyhydric alcohol compound is dispersed or dissolved in water or an organic solvent to a sliding surface of a metal bearing member to be coated, an iron oxide coating is applied to the surface. Can also be formed.

  The polyhydric alcohol compound that can be used in the present invention is derived from a plant described later. By subjecting the bearing member to a coating treatment using these compounds, it is possible to effectively prevent peeling on the rolling surface due to hydrogen embrittlement, and to provide a rolling bearing for automobile electrical equipment and auxiliary equipment with a low environmental load.

  Examples of plant-derived polyhydric alcohol compounds that can be used in the present invention include gallic acid, ellagic acid, chlorogenic acid, caffeic acid, quinic acid, curcumin, quercetin, pyrogallol, theaflavin, anthocyanin, rutin, lignan, catechin and the like. It is done. Polyhydric alcohol compounds obtained from plant-derived sesamin, isoflavones, coumarins and the like can also be used. Such polyhydric alcohol compounds may be used alone or in combination of two or more.

  Among these, gallic acid or its derivatives, ellagic acid or its derivatives, chlorogenic acid or its derivatives, caffeic acid or its derivatives, because it is easy to form an iron oxide film on the surface of the metal bearing member during the coating treatment. It is preferable to use quinic acid or its derivative, curcumin or its derivative, quercetin or its derivative.

Gallic acid used in the present invention is a polyhydric alcohol compound contained in fusinoki, tea leaves, etc., and has a structure represented by the following formula (1). Moreover, the ellagic acid used for this invention is a polyhydric alcohol compound contained in a red raspberry etc., and has a structure shown to following formula (2).

  Derivatives of gallic acid used in the present invention include gallic acid esters such as methyl gallate, ethyl gallate, propyl gallate, butyl gallate, pentyl gallate, hexyl gallate, heptyl gallate, octyl gallate, and gallic acid. Examples thereof include gallates such as bismuth. Moreover, the same derivative can be used also about ellagic acid.

Chlorogenic acid used in the present invention is a polyhydric alcohol compound contained in coffee beans and the like, and has a structure represented by the following formula (3).

Caffeic acid and quinic acid used in the present invention are polyhydric alcohol compounds obtained by hydrolysis of chlorogenic acid. Caffeic acid has a structure represented by the following formula (4), and quinic acid has a structure represented by the following formula (5). .

Curcumin used in the present invention is a polyhydric alcohol compound contained in turmeric and the like, and has a structure represented by the following formula (6).

Quercetin used in the present invention is a polyhydric alcohol compound contained in citrus fruits and has a structure represented by the following formula (7).

  All the polyhydric alcohol compounds used in the following examples used reagents manufactured by Tokyo Chemical Industry Co., Ltd.

Examples 1 to 7
A treatment solution was prepared by adding 0.5 g of the polyhydric alcohol compound shown in Table 1 to 99.5 g of the solvent shown in Table 1. A 6203 bearing (bearing dimensions: inner diameter 17 mm, outer diameter 40 mm, width 12 mm, material: SUJ2) is immersed in the treatment solution and rotated for 4 hours, and the entire surface of the metal bearing member of the rolling bearing is iron oxide. A film was formed. Grease (manufactured by NTN; E5 grease) was sealed in this bearing to obtain a rolling bearing test piece. The obtained rolling bearing test piece was subjected to the rapid acceleration / deceleration test shown below, and the peeling occurrence lifetime was measured. The results are also shown in Table 1.

<Rapid acceleration / deceleration test>
The rolling bearing test piece is mounted on a test machine as a rolling bearing that supports the rotating shaft that supports the pulley around the rotating belt of the alternator, which is an example of automobile electrical equipment and auxiliary equipment, and the rapid acceleration / deceleration test is performed. It was. The rapid acceleration / deceleration test conditions are as follows: the load load on the pulley attached to the tip of the rotating shaft is set to 1960 N, the operating speed is set to 0 rpm to 18000 rpm, and a current of 0.1 A flows through the test bearing. The test was conducted. Then, abnormal peeling occurred in the bearing, and the time spent until the vibration of the vibration detector exceeded the set value and the test machine stopped was measured as the peeling life time (time (h)).

Comparative Example 1
The same grease as in Example 1 was sealed in a 6203 bearing (bearing dimensions: inner diameter 17 mm, outer diameter 40 mm, width 12 mm) without subjecting the metal bearing member to surface treatment to obtain a rolling bearing test piece. The obtained rolling bearing test piece was subjected to the above-described rapid acceleration / deceleration test, and the peeling occurrence life time was measured. The results are also shown in Table 1.

  As shown in Table 1, Examples 1 to 7 exhibited excellent durability with a lifetime of 480 hours or more in the rapid acceleration / deceleration test. This is presumably because an iron oxide film is formed by a specific polyhydric alcohol compound, generation of hydrogen due to decomposition of grease is suppressed, and unique peeling due to hydrogen embrittlement on the bearing rolling surface can be prevented. On the other hand, in Comparative Example 1, the life was shorter than in Examples 1 to 7.

  Since the rolling bearing for automobile electrical equipment / auxiliary machinery of the present invention is coated with a polyhydric alcohol compound derived from a plant on the sliding surface or rolling surface of at least one member selected from metal bearing members, Long life even under sudden acceleration / deceleration conditions. For this reason, it can be suitably used as a rolling bearing for automotive electrical parts such as alternators, car air conditioner electromagnetic clutches, fan coupling devices, intermediate pulleys, and electric fan motors, and auxiliary machines.

DESCRIPTION OF SYMBOLS 1 Rolling bearing 2 Inner ring 3 Outer ring 4 Rolling body 5 Cage 6 Seal member 7 Grease 8a, 8b Opening 9 Cooling fan 10 Case 11 Oil chamber 12 Stirring chamber 13 Partition plate 14 Port 15 Spring 16 Bimetal 17 Piston 18 Drive disk 19 Flow hole 20 Drive shaft 21a, 21b Frame 22 Rotor 23 Rotor rotating shaft 24 Rotor coil 25 Stator 26 Stator coil 27 Pulley 28 Pulley body

Claims (11)

A rolling bearing for automobile electrical equipment and auxiliary equipment that rotatably supports a rotating shaft that is driven to rotate by engine output on a stationary member,
The automotive electrical equipment / auxiliary rolling bearing includes, as metal bearing members, an inner ring, an outer ring, a plurality of rolling elements interposed between the inner and outer rings, and a cage for holding the rolling elements. ,
At least one selected from the metal bearing members is a member in which a sliding treatment or a rolling surface of the member is coated with a plant-derived polyhydric alcohol compound.・ Rolling bearings for auxiliary machinery.   The rolling bearing for automobile electrical equipment / auxiliary machinery according to claim 1, wherein the member subjected to the coating treatment is at least one selected from the inner ring and the outer ring.   The rolling bearing for automobile electrical equipment and auxiliary equipment according to claim 1, wherein the member subjected to the coating treatment has an iron oxide coating on a sliding surface or a rolling surface of the member.   The coating treatment is a treatment of immersing the metal bearing member to be coated in a treatment liquid in which the plant-derived polyhydric alcohol compound is dispersed or dissolved in water and / or an organic solvent. The rolling bearing for automobile electrical equipment and auxiliary equipment according to claim 1, claim 2, or claim 3.   The rolling bearing for automobile electrical equipment / auxiliary machinery according to any one of claims 1 to 4, wherein the plant-derived polyhydric alcohol compound is curcumin or a derivative thereof.   The rolling bearing for automobile electrical equipment / auxiliary machinery according to any one of claims 1 to 4, wherein the plant-derived polyhydric alcohol compound is quercetin or a derivative thereof.   The rolling bearing for automobile electrical equipment / auxiliary machinery according to any one of claims 1 to 4, wherein the plant-derived polyhydric alcohol compound is chlorogenic acid or a derivative thereof.   The rolling bearing for automobile electrical equipment / auxiliary machinery according to any one of claims 1 to 4, wherein the plant-derived polyhydric alcohol compound is caffeic acid or a derivative thereof.   The rolling bearing for automobile electrical equipment / auxiliary machinery according to any one of claims 1 to 4, wherein the plant-derived polyhydric alcohol compound is quinic acid or a derivative thereof.   The rolling bearing for automobile electrical equipment / auxiliary machinery according to any one of claims 1 to 4, wherein the plant-derived polyhydric alcohol compound is gallic acid or a derivative thereof.   The rolling bearing for automobile electrical equipment / auxiliary machinery according to any one of claims 1 to 4, wherein the plant-derived polyhydric alcohol compound is ellagic acid or a derivative thereof.

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