JP2011021676A - Rolling bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lightweight rolling bearing device which can prevent a part of peripheral surface side with respect to a part of a raceway surface from creeping, and a raceway surface accuracy from deteriorating in an outside raceway member. <P>SOLUTION: In the rolling bearing device, a pulley 2 is fixed to a peripheral surface of an outer ring 10 of a ball bearing 1 by being out-fitted by press fit, the pulley 2 is formed by powder metallurgy processing using aluminum powder and iron powder, an inner circumferential side of the pulley 2 is composed by iron, and a peripheral side of the pulley 2 is composed by aluminum, an intermediate section of the pulley 2 is composed by an alloy of iron and aluminum, and the intermediate section of the pulley 2 is formed so that a composition ratio of aluminum weight with respect to a sum of aluminum weight and iron weight will increase monotonously toward the radial outside. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rolling bearing device that includes an inner race member, an outer race member, and rolling elements, and in which a belt is wound around the outer peripheral surface of the outer race member.

  Conventionally, as a rolling bearing device, there is one described in JP 2006-83926 A (Patent Document 1).

  This rolling bearing device includes a magnesium alloy pulley and a steel ball bearing, and the inner peripheral surface of the pulley is fitted and fixed to the outer peripheral surface of the outer ring of the ball bearing. A belt is wound around the outer peripheral surface of the pulley. This rolling bearing device uses a magnesium alloy pulley having a small mass to reduce the weight, and realizes improvements in fuel consumption, handling, and the like of a vehicle having the rolling bearing device.

  In this rolling bearing device, an annular groove is formed on the outer peripheral surface of the outer ring, and an annular projecting portion that protrudes radially inward from the inner peripheral surface of the pulley is formed on the pulley. The protruding portion of the pulley is fitted into the annular groove. In this way, relative rotation of the pulley with respect to the outer ring is prevented.

  In the conventional rolling bearing device, the accuracy of the raceway groove of the outer ring may be deteriorated due to the formation of the annular groove on the outer peripheral surface of the outer ring to prevent relative rotation of the pulley with respect to the outer ring.

  On the other hand, in order to avoid the deterioration of the accuracy of the raceway groove of the outer ring, if the cylindrical inner peripheral surface of the magnesium alloy pulley is externally fitted and fixed to the cylindrical outer peripheral surface of the outer ring of the rolling bearing, the magnesium alloy Due to the difference in coefficient of linear expansion from steel, the allowance between the pulley and the outer ring becomes small at high temperatures, and the pulley may creep with respect to the outer ring. And this creep may shorten the life of the rolling bearing device.

JP 2006-83926 A

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a lightweight rolling bearing that can prevent creeping of the outer circumferential surface portion of the outer race member with respect to the raceway surface portion and that does not cause deterioration of the accuracy of the raceway surface of the outer race member. To provide an apparatus.

In order to solve the above problems, the rolling bearing device of the present invention is
An inner race member having a raceway surface on the outer periphery;
An annular outer race member having a raceway surface on the inner periphery;
A rolling element disposed between the raceway surface of the inner raceway member and the raceway surface of the outer raceway member;
The outer race member is made of a metal material containing aluminum and iron,
A belt is wound around the outer peripheral surface of the outer race member,
A certain range in the radial direction from the radially inner end of the outer race member extends from the radial direction of the outer race member to the sum of the weight of the aluminum and the weight of the iron. The composition ratio of weight is reduced.

  The outer race member may be composed of a plurality of separate members or may be integrated. For example, the outer race member may be composed of an outer ring of a rolling bearing and a pulley externally fitted to the outer ring. The outer race member may have a structure in which an outer ring of a rolling bearing and a pulley are integrally formed.

  Further, the above-mentioned “a certain range in the radial direction from the radially inner end portion of the outer race member is the difference between the weight of aluminum and the weight of iron as it goes outward in the radial direction of the outer race member. The phrase “the composition ratio of the weight of iron to the sum is reduced” is the sum of the weight of aluminum and the weight of iron as it goes radially outward in a part of the certain range of the outer race member. When the composition ratio of the weight of iron to the iron does not change, while the composition ratio of the weight of iron to the sum of the weight of aluminum and the weight of iron decreases in the entire fixed range of the outer race member Shall also be included.

  Further, in this specification, the composition ratio of the weight of iron to the sum of the weight of aluminum and the weight of iron (hereinafter referred to as iron weight composition ratio) is expressed as iron mass [g] / (aluminum mass [g]. + Iron mass [g]).

  Further, in this specification, the composition ratio of the weight of aluminum to the sum of the weight of aluminum and the weight of iron (hereinafter referred to as aluminum weight composition ratio) is expressed as mass of aluminum [g] / (mass of aluminum [g] + It is defined by the mass of iron [g]).

  Therefore, in the above wording, for example, when the outer race member is constituted by an outer ring and a pulley externally fitted to the outer ring, there is no aluminum in the entire outer ring, and the pulley has a radially outer side. The case where the iron weight composition ratio decreases as the direction goes is also included.

  This is because, in the entire outer ring, the iron weight composition ratio is constant at 1 as it goes outward in the radial direction, whereas in the pulley, the iron weight composition ratio is from 1 as it goes outward in the radial direction. This is because it decreases.

  According to the present invention, the iron weight composition ratio decreases from the radially inner end of the outer race member to the radially outer range of the outer race member as it goes outward in the radial direction. Thus, the iron content at the end on the inner raceway surface side in the radial direction of the outer raceway member is increased. Accordingly, it is possible to increase the iron content on the raceway surface, which requires hardness and preferably has a high iron content. In addition, in the surface layer part of a raceway surface, it is preferable in the content rate of aluminum being zero (0).

  Further, according to the present invention, the iron weight composition ratio decreases as going outward in the radial direction in the certain range of the outer race member, so that the weight is reduced compared to the iron outer race member. Can be realized.

  Further, according to the present invention, when the outer race member is composed of a steel outer ring and a pulley externally fitted to the outer ring, the iron weight composition ratio increases toward the radially outer ring side in the pulley. By increasing the iron weight composition ratio, the difference in linear expansion coefficient between the radially inner portion of the pulley and the steel outer ring is reduced. Therefore, in this case, it is possible to suppress the tightening allowance between the pulley and the outer ring at high temperatures, and to suppress the pulley from creeping with respect to the outer ring.

  In addition, according to the present invention, since the creep is unlikely to occur, it is not necessary to form mechanical means for preventing creep on the outer race member. Therefore, the accuracy of the raceway surface of the outer race member due to the formation of the mechanical means does not occur.

In one embodiment,
At least a part of the outer race member is manufactured by a powder metallurgy method using a powder containing iron powder and aluminum powder.

  The present inventor conducted a number of tests, and in such a method that there exists an interface between a region where the iron weight composition ratio is 0 and a region where the iron weight composition ratio is 1, When trying to join aluminum, I discovered that joining iron and aluminum would not work.

  On the other hand, the present inventor tries to join iron and aluminum by powder metallurgy so that there is no boundary between iron powder and aluminum so that the iron weight composition ratio gradually increases in one direction. In this case, it was confirmed that the joining of iron and aluminum was successful.

  According to the above embodiment, since at least a part of the outer race member is manufactured by powder metallurgy, the distribution of fluctuations in the radial direction of the iron weight composition ratio is desired in at least a part of the outer race member. The distribution can be close to the distribution of fluctuations.

  Further, according to the embodiment, in a certain radial range from the radially inner end of the outer race member, the iron weight composition ratio increases as going outward in the radial direction of the outer race member. Since it is gradually reduced, aluminum and iron can be joined well. Therefore, it is possible to realize both weight reduction by containing aluminum and securing of the hardness of the raceway surface due to the large content of iron at the radially inner end.

  Moreover, according to the said embodiment, since at least one part of the said outer track member is manufactured by the powder metallurgy method, an outer track member can be manufactured easily and cheaply.

In one embodiment,
The average particle size of the iron particles of the iron powder is different from the average particle size of the aluminum particles of the aluminum powder.

  According to the above embodiment, since the average particle size of the iron particles of the iron powder is different from the average particle size of the aluminum particles of the aluminum powder, the one with the smaller average particle size in the gap between the particles with the larger average particle size Particles can easily enter, and the sealing performance at the boundary region between the two particles can be improved. Therefore, since it is in a close contact state in a powder state, it can be prevented that the boundary surface is peeled off or a defect is formed when it is hardened by sintering. Therefore, the outer race member can have a functionally gradient material in which iron and aluminum are in close contact.

In one embodiment,
The outer surface layer portion in the radial direction of the outer race member is located radially outward from the certain range of the outer race member,
The composition ratio of the weight of iron to the sum of the weight of aluminum and the weight of iron in the outer surface layer portion in the radial direction of the outer race member is the weight of aluminum and the weight of iron in the certain range of the outer race member. Is greater than the minimum composition ratio of the weight of iron to the sum of

  The surface layer on the outer peripheral surface around which the belt of the outer race member is wound easily wears due to dust and friction with the belt.

  According to the embodiment, since iron is present in the outer surface layer portion in the radial direction, wear on the outer peripheral surface of the outer race member can be suppressed by the iron existing in the surface layer. Therefore, the lifetime of the outer race member can be extended.

  According to the rolling bearing device of the present invention, in the outer race member, the creep of the outer peripheral surface portion with respect to the raceway surface portion can be suppressed, and the accuracy of the raceway surface of the outer race member does not deteriorate.

  Further, according to the rolling bearing device of the present invention, both the weight reduction of the outer race member and the securing of the hardness of the raceway surface can be realized easily and inexpensively.

  Further, according to the rolling bearing device of the present invention, it is possible to realize improvement in fuel consumption, improvement in handleability, etc. of a vehicle or the like having this outer race member.

It is a schematic cross section of the axial direction of the rolling bearing apparatus of 1st Embodiment of this invention. It is a schematic diagram which shows the arrangement | positioning state of the iron particle and aluminum particle in the local part of the pulley of the said rolling bearing apparatus. It is a schematic cross section of the axial direction of the rolling bearing apparatus of 2nd Embodiment of this invention. It is a schematic cross section of the axial direction of the rolling bearing apparatus of 3rd Embodiment of this invention.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic cross-sectional view in the axial direction of a rolling bearing device according to a first embodiment of the present invention.

  As shown in FIG. 1, the rolling bearing device includes a ball bearing 1 as an example of a rolling bearing and an annular pulley 2, and the ball bearing 1 includes an outer ring 10, an inner ring 11 as an example of an inner race member, and a plurality of rolling bearings. Ball 12 and two shield plates (not shown). The outer ring 10 and the pulley 2 constitute an outer race member. The outer ring 10 has a raceway groove as a raceway surface on the inner peripheral side thereof, while the inner ring 11 has a raceway groove as a raceway surface on the outer periphery thereof.

  Each of the outer ring 10, the inner ring 11 and the ball 12 is made of a steel material such as SUJ2 steel (high carbon chromium bearing steel), carburized and quenched steel such as SAE5120 carburized and quenched, and high-speed tool steel. The plurality of balls 12 are arranged between the raceway grooves of the outer ring 10 and the raceway grooves of the inner ring 11 at intervals in the circumferential direction while being held by a cage (not shown). . The one shield plate is disposed so as to block one axial opening of the outer ring 10 and the inner ring 11, while the other shield plate is arranged in the axial direction of the outer ring 10 and the inner ring 11. It arrange | positions so that the other opening may be plugged up.

  The pulley 2 has a substantially E-shaped cross section and includes an inner cylindrical portion 21, an outer cylindrical portion 22, and a connecting portion 23. The outer cylindrical portion 22 is disposed substantially concentrically with the inner cylindrical portion 21 and is located outward in the radial direction of the inner cylindrical portion 21. The connecting portion 23 extends in the radial direction of the inner cylindrical portion 21 and connects the inner cylindrical portion 21 and the outer cylindrical portion 22. The inner peripheral surface of the inner cylindrical portion 21 is tightly fitted to the outer peripheral surface of the outer ring 10 by press fitting. On the other hand, a belt is wound around the outer peripheral surface of the outer cylindrical portion 22.

  The pulley 2 constituting a part of the outer race member is manufactured by a powder metallurgy method using a powder containing iron powder and aluminum powder. Here, in the first embodiment, SMF4040 is used as the iron powder, and an aluminum alloy such as alloy number 6063 is used as the aluminum powder. Note that iron powders other than those described above may be used, and aluminum powders other than those described above may be used.

  The pulley 2 has an iron-weight composition ratio that decreases from the radially inner end of the pulley 2 toward the radially outward direction of the pulley 2. Specifically, in FIG. 1 showing the first embodiment and FIGS. 3 and 4 showing the following embodiments, the higher the gray scale gray level, the higher the iron weight composition ratio. And As shown in FIG. 1, the inner surface layer portion in the radial direction of the inner cylindrical portion 21 of the pulley 2 has an iron weight composition ratio of 1. In addition, the iron weight composition ratio decreases monotonously and gradually from the surface layer portion to the radially central portion of the outer cylindrical portion 22, and the radial direction of the outer cylindrical portion 22 decreases. It is 0 (zero) at the center. Further, the iron weight composition ratio is 0 from the radial center of the outer cylindrical portion 22 to the outer end of the outer cylindrical portion 22 in the radial direction, and the aluminum content in that region is 100%. . In the first embodiment, the radial range 60 of the outer race member is the entire radial range of the outer race member.

  Specifically, the pulley 2 is formed as follows.

  First, an aluminum powder and an iron powder are prepared. Here, in the first embodiment, the average particle size of the prepared iron powder is smaller than the average particle size of the prepared aluminum powder.

  Next, the above two powders are mixed. In this mixing, it arrange | positions so that the ratio of the aluminum powder with respect to iron powder and aluminum powder may become high gradually as it goes to the radial direction of a pulley to the metal mold | die of a pulley. Also, in the location corresponding to the radially inner end of the mold pulley, only iron powder is placed, while in the location corresponding to the radially outer end of the mold pulley, Place only aluminum powder.

  Subsequently, compression molding is performed. In compression molding, pressure is applied to the powder filled in the mold with upper and lower punches to form a compact called green compact or green compact. It is necessary that the prepared green compact has sufficient strength because the powder particles adhere to each other.

  Thereafter, sintering is performed. The green compact is fragile because it has sufficient adhesion between the powder particles but does not yet have an atomic bond. Therefore, sintering is performed by appropriately adjusting the sintering temperature, the sintering time, and the gas atmosphere in the sintering furnace. By sintering, the green compact is baked and hardened at a high temperature to make it sufficiently strong. In addition, as a method for performing both compression molding and sintering, there are a hot press method in which powder packed in a mold is compressed while heating, and a hot isostatic press method in which compression molding is performed in a high-temperature and high-pressure gas container. It can also be used. In this way, the pulley 2 is created. In addition, you may perform sintering using the discharge plasma sintering method (SPS) which flows by flowing a large electric current.

  FIG. 2 is a schematic diagram showing an arrangement state of the iron particles 127 and the aluminum particles 120 in a local portion of the pulley 2 of the rolling bearing device. In FIG. 2, an arrow A indicates the radial direction, and the upper side of the drawing is the outer side in the radial direction. Moreover, FIG. 2 is a figure which shows a principle and the dimension of the area | region where the aluminum particle 120 and the iron particle 127 are mixed in a radial direction differs from an actual dimension.

  As shown in FIG. 2, in this example, many aluminum particles 120 have substantially the same particle diameter, and many iron particles 127 also have substantially the same particle diameter. The average particle size of the aluminum particles 120 is larger than the average particle size of the iron particles 127. As shown in FIG. 2, in a region where the aluminum particles 120 and the iron particles 127 are mixed in the radial direction, the iron particles 127 having a small average particle diameter enter between the aluminum particles 120 having a large average particle diameter. Thus, the gap is small and a dense state is realized.

  According to the rolling bearing device of the first embodiment, the outer race member (the outer ring 10 and the pulley 2) goes outward in the radial direction of the outer race member from the radially inner end of the outer race member. Therefore, since the iron weight composition ratio is reduced from 1 to 0, the raceway surface can be constituted by a portion made only of iron. Therefore, the hardness of the raceway surface can be ensured and the raceway surface is not deformed.

  Further, according to the rolling bearing device of the first embodiment, the pulley 2 is made of iron because the iron weight composition ratio decreases and the aluminum weight composition ratio increases as it goes outward in the radial direction. The weight can be reduced as compared with the outer race member.

  Moreover, according to the rolling bearing device of the first embodiment, the iron weight composition ratio is increased so that the iron weight composition ratio becomes 1 in the pulley 2 toward the outer ring 10 side in the radial direction. The difference in linear expansion coefficient between the radially inner portion of the pulley 2 and the steel outer ring 10 is reduced. Therefore, it is possible to suppress the tightening allowance between the pulley 2 and the outer ring 10 at a high temperature, and to suppress the pulley 2 from creeping with respect to the outer ring 10.

  Further, according to the rolling bearing device of the first embodiment, since the creep is unlikely to occur, it is not necessary to form mechanical means for preventing creep on the outer race member. Therefore, the accuracy of the raceway surface of the outer race member due to the formation of the mechanical means does not occur.

  In addition, the inventor conducted a number of tests, in such a way that there is an interface between the region where the iron weight composition ratio is 0 and the region where the iron weight composition ratio is 1, in the powder metallurgy method, When I tried to join iron and aluminum, I discovered that the iron and aluminum joint did not work.

  On the other hand, the present inventor tries to join iron and aluminum by powder metallurgy so that there is no boundary between iron powder and aluminum so that the iron weight composition ratio gradually increases in one direction. In this case, it was confirmed that the joining of iron and aluminum was successful.

  According to the rolling bearing device of the first embodiment, since the pulley 2 constituting a part of the outer race member is manufactured by the powder metallurgy method, the fluctuation in the radial direction of the iron weight composition ratio in the pulley 2 is achieved. Can be made close to the desired fluctuation distribution.

  Further, according to the rolling bearing device of the first embodiment, in a certain range in the radial direction from the radially inner end of the outer race member, as it goes outward in the radial direction of the outer race member, Since the iron weight composition ratio is gradually reduced, aluminum and iron can be bonded satisfactorily. Therefore, it is possible to realize both weight reduction by containing aluminum and securing of the hardness of the raceway surface due to the large iron content at the radially inner end.

  Moreover, according to the said embodiment, since the pulley 2 is manufactured by the powder metallurgy method, the pulley 2 can be manufactured simply and inexpensively, and the outer race member including the pulley 2 can be manufactured easily and inexpensively.

  Further, according to the rolling bearing device of the first embodiment, since the average particle size of the iron particles 127 is different from the average particle size of the aluminum particles 120, iron easily enters the gaps between the aluminum particles, and the boundary region The sealing performance can be improved. Therefore, since it is in a close contact state in a powder state, it can be prevented that the boundary surface is peeled off or a defect is formed when it is hardened by sintering. Therefore, the pulley 2 can have a functionally gradient material in which iron and aluminum are in close contact.

  In the rolling bearing device according to the first embodiment, a large number of aluminum particles 120 used for manufacturing the pulley 2 have substantially the same particle diameter, and a large number of iron particles 127 used for manufacturing the pulley 2 are included. The particle sizes were substantially the same, and the average particle size of the aluminum particles 120 was larger than the average particle size of the iron particles 127. However, in the present invention, the particle diameters of a large number of aluminum powders may vary widely, and the particle diameters of the aluminum particles may be different from each other. The difference in size may be different, and the particle sizes of the iron particles may be different from each other.

  In the present invention, the average particle size of the aluminum particles may be smaller than the average particle size of the iron particles. In the present invention, the average particle size of the aluminum particles and the average particle size of the iron particles may be substantially the same.

  Further, in the rolling bearing device of the above embodiment, the rolling bearing is the ball bearing 1, but in this invention, the rolling bearing is a double-row ball bearing, but it is a roller bearing (cylindrical roller bearing, tapered roller bearing). , Spherical roller bearings) or the like, and the rolling elements may be balls arranged in a double row or rolling elements other than balls such as rollers.

  Further, in the rolling bearing device of the above embodiment, the iron weight composition ratio starts from 1 as it goes from the radially inner surface layer portion of the inner cylindrical portion 21 of the pulley 2 to the radially central portion of the outer cylindrical portion 22. It gradually decreased to zero. However, in this invention, for example, the iron weight composition ratio gradually increases from 1 to 0 as it goes from the radially inner surface layer portion of the inner cylindrical portion of the pulley to the radially outer end portion of the outer cylindrical portion. You may make it decrease to. In short, the present invention requires that the iron weight composition ratio of the outer race member is reduced within a certain range in the radial direction of the outer race member from the radially inner end of the outer race member. Any shape and form may be used.

  FIG. 3 is a schematic cross-sectional view in the axial direction of the rolling bearing device of the second embodiment.

  In the rolling bearing device according to the second embodiment, the outer surface layer in the radial direction of the pulley 102 includes an iron component of 5 to 40% by weight of the total mass of the surface layer, and not the outer cylindrical portion 122. Thus, the connection portion 123 differs from the rolling bearing device of the first embodiment in that a layer having an aluminum mass composition ratio of 1 appears.

  Also in the rolling bearing device of the second embodiment, the pulley 102 is manufactured by powder metallurgy.

  In the rolling bearing device of the second embodiment, the same components as those of the rolling bearing device of the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  In the rolling bearing device of the second embodiment, the description of the operations and effects common to those of the rolling bearing device of the first embodiment will be omitted, and the configurations, functions, and effects different from those of the rolling bearing device of the first embodiment will be omitted. Only the modification will be described.

  The outer peripheral surface of the outer cylindrical portion 122 of the pulley 102 is easily worn by dust and is easily worn by sliding of the belt. In the rolling bearing device of the second embodiment, this problem is improved.

  In the rolling bearing device of the second embodiment, the iron weight composition ratio is 1 in the surface layer portion on the inner peripheral side of the inner cylindrical portion 121 of the pulley 102. Further, the iron weight composition ratio gradually decreases monotonically as it goes to the vicinity of the central portion of the connecting portion 123 radially outward from the surface layer portion on the inner peripheral side of the inner cylindrical portion 121, and the central portion of the connecting portion 123 In the vicinity, the iron weight composition ratio is 0 (aluminum weight composition ratio is 1).

  Further, the aluminum weight composition ratio is 1 until just before the surface layer portion (range from the outer peripheral surface of the outer cylindrical portion 122 of the pulley 102 to several mm in the depth direction) 161 of the outer cylindrical portion 122 of the pulley 102. Further, in the surface layer portion 161 of the outer cylindrical portion 122 of the pulley 102, the weight percent of iron with respect to the total mass of the surface layer portion 161 is 5 to 40 weight percent. The surface layer portion 161 of the outer cylindrical portion 122 of the pulley 102 is the outer surface layer portion in the radial direction of the outer race member.

  In the second embodiment, the constant radial range 160 of the outer race member is the entire outer region of the outer ring 10 and the outer surface of the pulley 102 from the outer peripheral surface layer portion of the inner cylindrical portion 121 in the radial direction of the pulley 102. The portion of the cylindrical portion 122 up to just before the surface layer portion 161 is configured.

  According to the rolling bearing device of the second embodiment, since iron is present in the surface layer portion 161 of the outer cylindrical portion 122 of the pulley 102, the wear resistance of the outer peripheral surface of the pulley 102 due to the iron present in the surface layer portion 161. The wear can be suppressed. Therefore, the life of the pulley 102 can be extended.

  FIG. 4 is a schematic cross-sectional view in the axial direction of the rolling bearing device of the third embodiment.

  The rolling bearing device of the third embodiment is significantly different from the first and second embodiments in that the outer race member is not composed of an outer ring and a pulley of the rolling bearing, and the outer race member is an integral member. .

  In the rolling bearing device of the third embodiment, the description of the operational effects and modifications common to the rolling bearing device of the first or second embodiment is omitted, and the rolling bearing device of the first or second embodiment is omitted. Only different configurations, operational effects, and modifications will be described.

  This rolling bearing device includes an inner ring 211 as an inner race member, an annular outer race member 210, a ball 212 as a rolling element, and two shield plates (not shown). The inner ring 211 has a raceway groove as a raceway surface on the outer periphery, and the outer race member 210 has a raceway groove as a raceway surface on the inner periphery.

  Each of the inner ring 211 and the ball 212 is made of a steel material such as SUJ2 steel (high carbon chromium bearing steel), carburized and hardened steel such as SAE5120 carburized and hardened, and high-speed tool steel.

  The plurality of balls 12 are arranged at intervals in the circumferential direction between the raceway grooves of the outer raceway member 210 and the raceway grooves of the inner ring 211 while being held by a cage (not shown). ing. The one shield plate is disposed so as to close one axial opening of the outer race member 210 and the inner ring 211, while the other shield plate includes the outer race member 210, the inner ring 211, and the outer race member 210. It arrange | positions so that the other opening of this axial direction may be plugged up.

  The outer race member 210 is manufactured by the powder metallurgy method described in detail in the first embodiment. Specifically, the outer race member 210 is made by powder metallurgy so that the outer peripheral side is iron, the middle is aluminum, and the inner peripheral side is iron. Further, the boundary between aluminum and iron is made of an alloy of aluminum and iron. Specifically, between the outer peripheral side and the middle, the component ratio of aluminum gradually increases from the outer peripheral side to the middle, so that the material has an inclination function to ensure the joining. ing. In addition, between the middle and the inner circumferential side, the component ratio of iron gradually increases from the middle to the inner circumferential side, so that the material has an inclination function, so that the joining can be ensured. I have to. In the third embodiment, the average particle size of aluminum is set to a particle size different from the average particle size of iron so that the bonding is dense.

  Further, the surface layer portion 270 on the inner peripheral side of the outer race member 210 is hardened by high frequency to be hardened so that it can function as a raceway groove.

  According to the rolling bearing device of the third embodiment, since the outer race member 210 integrated with the outer ring pulley having the functionally gradient material is used, a lightweight rolling bearing device that can reliably suppress creep can be realized.

  Further, according to the rolling bearing device of the third embodiment, since the outer ring and the pulley are integrated, the number of parts can be reduced, and the handleability can be greatly improved.

  Further, according to the rolling bearing device of the third embodiment, since the outer peripheral side of the outer race member 210 is made of iron, the wear resistance due to dust and friction with the belt is as excellent as that of an iron pulley. Can be a thing. Needless to say, when the wear of the pulley is not a problem, such as when the back surface of the belt is made of rubber, there is no outermost iron portion and the outermost periphery may be made of aluminum.

DESCRIPTION OF SYMBOLS 1 Ball bearing 2,102 Pulley 10 Outer ring 11, 211 Inner ring 12,212 Ball 60 Fixed range of radial direction of outer race member 120 Aluminum particle 127 Iron particle 161 Surface layer portion of outer cylindrical portion of pulley 210 Outer race member

Claims (4)

An inner race member having a raceway surface on the outer periphery;
An annular outer race member having a raceway surface on the inner periphery;
A rolling element disposed between the raceway surface of the inner raceway member and the raceway surface of the outer raceway member;
The outer race member is made of a metal material containing aluminum and iron,
A belt is wound around the outer peripheral surface of the outer race member,
A certain range in the radial direction from the radially inner end of the outer race member extends from the radial direction of the outer race member to the sum of the weight of the aluminum and the weight of the iron. A rolling bearing device characterized in that the composition ratio of weight is reduced. The rolling bearing device according to claim 1,
At least a part of the outer race member is manufactured by a powder metallurgy method using a powder containing iron powder and aluminum powder. In the rolling bearing device according to claim 2,
The rolling bearing device according to claim 1, wherein an average particle diameter of the iron particles of the iron powder is different from an average particle diameter of the aluminum particles of the aluminum powder. In the rolling bearing device according to any one of claims 1 to 3,
The outer surface layer portion in the radial direction of the outer race member is located radially outward from the certain range of the outer race member,
The composition ratio of the weight of iron to the sum of the weight of aluminum and the weight of iron in the outer surface layer portion in the radial direction of the outer race member is the weight of aluminum and the weight of iron in the certain range of the outer race member. A rolling bearing device characterized in that it is larger than the minimum composition ratio of the weight of iron with respect to the sum.