JP2002266870A - Rolling bearing, its manufacturing method, and rotating machine device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure a sufficient durability in a rotating machine device by preventing abrasion at surfaces of a housing 1b and an outer ring 4a which are brought into sliding contact with each other even when a creep is generated between the housing 1b and the outer ring 4a. SOLUTION: A coat 16 made of thermosetting synthetic resin is formed on the surface of the outer ring 4, whereby an outer peripheral surface or the like of the outer ring 4a is brought into contact with an inner peripheral surface or the like of the housing 1b via the coat 16 in an assembling state. Since the coat 16 has sufficiently small coefficient of friction and excellent abrasion resistance, the above problem can be solved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a rolling bearing, a method of manufacturing the same, and a rotary mechanical device, for example, various rotary mechanical devices such as an automobile transmission and a motor, and a rolling bearing incorporated in a rotary support portion of the rotary mechanical device. Regarding improvement. In particular, the present invention prevents abrasion of the surfaces of these two members that come into sliding contact with each other when the outer ring that constitutes the rolling bearing is rotated unintentionally inside the housing that constitutes the rotary mechanical device. In addition, the present invention relates to a technique for sufficiently securing the durability of the rotation support portion.

[0002]

2. Description of the Related Art For example, as shown in FIG.
The shaft member 3 is rotatably supported by a plurality of rolling bearings (ball bearings in the illustrated example) 2 and 2 inside the inside.
Further, in the assembled state shown in the drawing, each of the rolling bearings 2, 2
, Each outer ring 4 on the inner peripheral surface of the housing 1,
Each inner ring 5 is fitted and supported on the outer peripheral surface of the shaft member 3 by interference fit or the like.

[0003] In the case of various types of rotating machinery such as the above-mentioned transmission for automobiles, the housing 1 is often made of an aluminum alloy in order to reduce the weight of the rotating machinery. However, the coefficient of thermal expansion of the aluminum alloy forming the housing 1 is larger than the coefficient of thermal expansion of the bearing steel forming the outer ring 4. Therefore, when no measures are taken, the interference of the outer ring 4 with respect to the housing 1 is reduced (or lost) when the temperature rises during operation, and the outer ring 4 rotates inside the housing 1. So-called creep may occur. For example, even when a margin for preventing creep is provided up to about 60 ° C., the temperature at the time of use of the rotating mechanical device as described above often exceeds 60 ° C., so that the above-described creep is easily generated. . If the fitting surface between the outer race 4 and the housing 1 has no interference, creep may occur even at room temperature.

In addition, such a creep is achieved by connecting at least one of the housing 1 and the shaft member 3 (only the shaft member 3 in the example shown in FIG. 5) to a plurality of members which are separate bodies. When the (axial elements 7a and 7b) are configured to be combined with each other, it may easily occur. That is, if at least one of the housing 1 and the shaft member 3 is configured by combining a plurality of members that are separate bodies with each other, an assembling error and a processing error that are unavoidable in manufacturing. , The central axes of these members tend to be eccentric to each other. In such an eccentric state, the radial load applied between the outer ring 4 constituting the rolling bearing 2 and the housing 1 increases in a part of the circumferential direction, and the outer ring 4 The state becomes close to rolling contact. As a result, the creep is liable to occur. As shown in FIG. 6, both the housing 1a and the shaft member 3 are connected to a plurality of members (housing elements 6a and 6b,
When the shaft elements 7a and 7b are combined with each other, the possibility that creep is likely to occur for the above-described reason is further increased.

In any case, when the above-described creep occurs, the fitting surfaces of the housing 1 (1a) and the outer race 4 (the surfaces that come into sliding contact with each other when creep occurs) are abnormally worn. As a result, rattling occurs in the rotation support portion of the rotary machine, and the performance of the rotary machine is deteriorated.

In order to prevent such inconvenience, as a technique for preventing the occurrence of the creep, a pin implanted in a part of the housing 1 (1a) has been conventionally used.
(See Japanese Utility Model Laid-Open Publication No. 51-148544) or an eccentric ring made of synthetic resin in an eccentric groove formed on the outer peripheral surface of the outer ring 4 over the entire circumference. When the outer ring 4 tends to rotate inside the housing 1 (1a), the eccentric ring is moved between the bottom surface of the eccentric groove and the inner peripheral surface of the housing 1 (1a). Or an O-ring made of an elastic material mounted in a groove formed on the outer peripheral surface of the outer ring 4 over the entire circumference, and the bottom surface of the groove and the housing. 1 (1a) is compressed in the radial direction with the inner peripheral surface, and a part of the O-ring is
(1a) Engagement into a concave groove formed in a part of the inner peripheral surface in the circumferential direction (Japanese Patent Laid-Open No. 10-299785, etc.) or a concave groove formed over the entire outer peripheral surface of the outer ring 4 A resin ring made of a synthetic resin having a larger coefficient of thermal expansion than the bearing steel constituting the outer ring 4 is inserted therein, and the resin ring which expands when the temperature rises is fitted to the bottom surface of the groove and the inner peripheral surface of the housing. (For example, Japanese Patent Application Laid-Open No. 9-269909) is known.

However, in the case of the above-described technique for preventing the generation of creep, the processing cost for forming the receiving hole, the eccentric groove, the concave groove, etc., the pin, the eccentric ring, and the The cost of parts such as the O-ring and the resin ring increases, and the outer ring 4 for the housing 1 (1a) is increased.
There is a problem that the assembling work becomes troublesome. Further, there is a possibility that the strength of the member having the receiving hole or the concave groove is reduced, or the pin, the eccentric ring, the O-ring, the resin ring, and the like are damaged. is there.

On the other hand, even when creep occurs as described above, the housing 1 (1a) and the outer race 4
Conventionally, as a technique capable of preventing the occurrence of abnormal wear or the like on the mating surface, molybdenum disulfide, graphite (graphite), tungsten disulfide, metal oxide, fluorine resin powder, or the like is applied to the outer peripheral surface of the outer ring 4. A technique for forming a contained solid lubricating coating is known. In the case of such a technique of forming a solid lubricating film, the outer peripheral surface of the outer ring 4 contacts the inner peripheral surface of the housing 1 (1a) via the solid lubricating film. For this reason, even when the creep occurs, the presence of the solid lubricating coating causes the housing 1
Abnormal wear and the like can be prevented from occurring on the fitting surface between (1a) and the outer ring 4. Further, since only a solid lubricating film is formed on the outer peripheral surface of the outer race 4, the disadvantages caused by the creep can be inexpensively solved. Also, the housing 1 (1
There is no trouble in assembling the outer ring 4 for a).

[0009]

However, in the case of the technique of forming a solid lubricating film on the surface of the outer race 4 as described above, if the solid lubricating film is worn and the surface of the outer race 4 is exposed, Abnormal wear of the fitting surface between the outer race 4 and the housing 1 (1a) cannot be prevented. Also, depending on the mounting location of the rolling bearing 2 including the outer ring 4, it may not be preferable that the wear powder of the solid lubricating film scatters around. For this reason, it is preferable to use a film having excellent wear resistance as a film formed on the surface of the outer ring 4. The rolling bearing, the method of manufacturing the same, and the rotating mechanical device of the present invention have been invented in view of the above-described circumstances.

[0010]

SUMMARY OF THE INVENTION Among the rolling bearings, the manufacturing method thereof, and the rotary machine device according to the present invention, the rolling bearing according to the first aspect has an outer race having an outer raceway on an inner peripheral surface and an inner race on an outer peripheral surface. An inner ring having a raceway, and a plurality of rolling elements rotatably provided between the outer raceway and the inner raceway are provided. The outer ring is used in a state where the outer ring is internally fitted to the housing and the inner ring is externally fitted to the shaft member. In particular, in the rolling bearing described in claim 1,
A coating made of a thermosetting synthetic resin is formed on at least a part of the surface of the outer race that comes into contact with the surface of the housing. As the thermosetting synthetic resin for forming the coating, various kinds of resins such as a phenol resin, an epoxy resin, a melamine resin, a urea resin, a silicone resin, a polyester resin, and a diallyl phthalate resin can be employed. Further, in the rolling bearing according to the second aspect, the thermosetting synthetic resin contains molybdenum disulfide.

According to a third aspect of the present invention, there is provided a method for manufacturing a rolling bearing according to any one of the first to second aspects, wherein a portion of the surface of the outer ring, which is in contact with the surface of the housing, for producing the rolling bearing. Is applied to at least a part of the resin by dissolving a thermosetting synthetic resin as described above (including the one containing molybdenum disulfide and the like), and then applying heat to evaporate the solvent, thereby A film made of a thermosetting synthetic resin is formed on the portion.

Further, the rotary mechanical device according to claim 4 is
In order to rotatably support the housing, the shaft member, and the shaft member with respect to the housing, the outer ring is internally fitted to the housing, and the inner ring is externally supported to the shaft member. A rolling bearing. The housing is made of a material having a larger coefficient of thermal expansion than the outer ring. In particular, in the rotary mechanical device described in claim 4, the rolling bearing is provided in claims 1 to 5.
2. The rolling bearing according to any one of 2.

[0013]

In the case of the rolling bearing of the present invention configured as described above, the method of manufacturing the same, and the rotary machine, the surface (outer peripheral surface, etc.) of the outer ring that forms the rolling bearing is the surface of the housing (the outer surface) that configures the rotary machine. (The inner peripheral surface, etc.) via a thermosetting synthetic resin film formed on the surface of the outer ring. Further, the coefficient of friction of the coating made of the thermosetting synthetic resin is sufficiently small. For this reason, even when creep occurs between the housing and the outer race, it is possible to prevent the surfaces of these two members slidingly contacting each other from being abnormally worn. Further, the coating formed by the thermosetting synthetic resin has excellent wear resistance.
For this reason, the durability of each of the surfaces slidingly contacting each other can be sufficiently ensured. In addition, since the wear powder of the coating is hardly generated,
Keep the surroundings clean. Further, since the coating is merely formed on the outer peripheral surface of the outer race, the inconvenience caused by the creep can be solved at a low cost. Also, there is no trouble in assembling the outer ring to the housing.

[0014]

FIG. 1 shows a first embodiment of the present invention.
An example is shown. A shaft member 3a is rotatably supported by a ball bearing 8 which is a rolling bearing inside a housing 1b made of an aluminum alloy constituting various rotating mechanical devices such as a transmission and a motor for an automobile. This ball bearing 8 has an outer race 4 having a deep groove type outer raceway 9 on the inner peripheral surface.
and an inner ring 5a having a deep groove type inner ring raceway 10 on the outer peripheral surface.
And a plurality of balls 11, each of which is a rolling element, provided rotatably between the outer race 9 and the inner race 10. The plurality of balls 11 may be held by a holder (not shown).

In the assembled state shown in the figure, the outer race 4a is internally fitted to the housing 1b by interference fitting (or by intermediate fitting or clearance fitting). At the same time, the outer ring 4a is sandwiched between a stepped surface 12 formed on the inner peripheral surface of the housing 1b over the entire periphery and a spacer 13 internally fitted on the inner peripheral surface of the housing 1b. The outer ring 4a is positioned in the axial direction. Further, the inner ring 5a is externally fitted and fixed to the shaft member 3a by interference fitting or the like. At the same time, the inner ring 5a is clamped between a step surface 14 formed over the entire outer periphery of the shaft member 3a and a spacer 15 externally fitted to the shaft member 3a. Are positioned in the axial direction.

Particularly, in the case of this embodiment, molybdenum disulfide (MoS ₂ ) and antimony (Sb) are provided on the surface of the outer ring 4 a except for the outer ring raceway 9 (the portion shown by oblique lattice in FIG. 1). And the like, containing a thermosetting synthetic resin (for example,
A coating 16 made of phenol resin, epoxy resin, melamine resin, urea resin, silicon resin, polyester resin, diallyl phthalate resin, etc.) is formed. In the case of this example, such a coating 16 is formed by dissolving a solvent in which the thermosetting synthetic resin (containing MoS ₂ , Sb, etc.) is dissolved,
After applying to the surface of the outer ring 4a using a spray, a brush, or the like, the solvent is evaporated by applying heat (the thermosetting synthetic resin is baked on the surface of the outer ring 4a). The thickness of the coating 16 thus formed is about 0.001 to 0.05 mm. The coefficient of friction of the coating 16 is 0.05 to 0.09 in a dry state.
It is about. Therefore, when the outer ring 4a is assembled to the housing 1b as described above, the outer peripheral surface and both end surfaces of the outer ring 4a are the inner peripheral surface and the stepped surface 12 of the housing 1b, and the axial end surface of the spacer 13 respectively. , Via the coating 16.

In the case of the rolling bearing and the rotary machine of the present embodiment configured as described above, the outer peripheral surface and both end surfaces of the outer ring 4a are respectively formed on the inner peripheral surface and the step surface 1 of the housing 1b.
2 and the end face of the spacer 13 in the axial direction
Contact through. Further, the coefficient of friction of the coating 16 is sufficiently small as described above. For this reason, the housing 1
Even if creep occurs between the outer ring 4a and the outer ring 4a, the surfaces that come into contact (sliding contact) with each other, especially when worn, the repair becomes troublesome. Abnormal wear can be prevented. As a result, it is possible to prevent rattling of the rotation support portion of the rotary machine device. Further, the coating 16 formed of the thermosetting synthetic resin has excellent durability. Therefore, the life of the coating 16 is ensured, and the durability of each of the surfaces facing the coating 16 can be sufficiently ensured. Further, since the abrasion powder of the coating 16 is hardly generated, the surroundings can be kept clean. The coating 1 is applied to the surface of the outer ring 4a except for the outer ring raceway 9.
Since only 6 is formed, it is possible to prevent inconvenience caused by the above-mentioned creep at low cost. Also, there is no trouble in assembling the outer ring 4a to the housing 1b.

Next, an experiment performed to confirm the effect of the present invention will be described. In the experiment, a rolling bearing in which a coating made of a thermosetting synthetic resin was formed on the outer peripheral surface of the outer ring (a product of the present invention) and a rolling bearing in which a coating was not formed (a comparative product) were prepared. By operating each of these rolling bearings while generating creep between the outer ring and the housing, the relationship between the operating time of each of the rolling bearings and the amount of wear on the inner peripheral surface of the housing is examined. (FIG. 2). At the same time, the relationship between the operation time of the rolling bearing (product of the present invention) and the amount of wear of the coating formed on the outer peripheral surface of the outer ring was also examined (FIG. 3). Other test conditions are as follows. Housing material: Aluminum alloy (A5056) Outer ring material: High carbon chrome bearing steel Radial load applied to rolling bearing: 9600 [N] Rotation speed: 3000 [min ^-1 ]

First, as shown in the experimental results shown in FIG. 2, when the operation time of the rolling bearing reaches 100 [Hr], in the case of the comparative product, the amount of wear on the inner peripheral surface of the housing is reduced by about In contrast, in the case of the product of the present invention, the inner peripheral surface of the housing is hardly worn. From this fact, it can be seen that in the case of the product of the present invention, the inner peripheral surface of the housing can be hardly worn. Further, as shown in the experimental results shown in FIG. 3, the coating formed on the outer peripheral surface of the outer ring is hardly worn when the operation time of the rolling bearing has passed 100 [Hr]. From this, it is understood that in the case of the present invention, the effect that the inner peripheral surface of the housing can be hardly worn can be maintained for a long time. It can also be seen that abrasion powder of the coating can be hardly generated.

In practicing the present invention, the position where the coating 16 is formed on the surface of the outer race 4a can be variously selected as necessary. That is, as in the embodiment shown in FIG. 1, the coating 16 is formed on the surface of the outer ring 4a except for the outer ring raceway 9 (FIG. 4C). 4A is formed only on the outer peripheral surface {FIG.
It can be formed only on the outer peripheral surface and both axial end surfaces of the outer ring 4a (see FIG. 2B). When the groove 17 such as an eccentric groove or a concave groove for forming the above-described creep preventing structure is formed on the outer peripheral surface of the outer ring 4a, the coating 16 is used.
It can also be formed on the inner surface of the groove 17 (FIGS. (D) and (F)). Also, of the inner peripheral surface of the outer ring 4a,
At least one axial end has a seal ring 18, 1
8 (E) and the shield plate 19 (FIG. 9F), even when the peripheral portion is locked or slid, the coating 16 may be formed on the surface of the outer ring 4a. it can. or,
In the above description, a ball bearing is taken as an example of a rolling bearing. However, the present invention provides, in addition to a ball bearing, for example, a cylindrical roller bearing,
It can be applied to various rolling bearings such as tapered roller bearings.

[0021]

The rolling bearing, the method of manufacturing the same and the rotary machine of the present invention are constructed and operated as described above. Therefore, even when creep occurs between the housing and the outer ring, the rolling bearing and the rotating machine are in sliding contact with each other. Wear of the surfaces of both members can be prevented. For this reason, it is possible to prevent the occurrence of abnormal wear in each part of the rotary machine, and it is possible to reduce costs required for repair and inspection of the rotary machine. In addition, since abrasion powder of the film formed on the surface of the outer ring is hardly generated, the surroundings can be kept clean.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing an example of an embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between an operation time and a wear amount of an inner peripheral surface of a housing as a result of an experiment performed to confirm an effect of the present invention.

FIG. 3 is a graph showing a relationship between an operation time and a wear amount of a thermosetting synthetic resin.

FIG. 4 is a half sectional view of a rolling bearing showing six examples of the embodiment of the present invention.

FIG. 5 is a cross-sectional view showing a first example of the rotary mechanical device.

FIG. 6 is a sectional view showing the second example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 1a, 1b Housing 2 Rolling bearing 3 Shaft member 4, 4a Outer ring 5, 5a Inner ring 6a, 6b Housing element 7a, 7b Shaft element 8 Ball bearing 9 Outer ring raceway 10 Inner ring raceway 11 Ball 12 Stepped surface 13 Spacer 14 Stepped surface 15 Spacer 16 Coating 17 Groove 18 Seal ring 19 Shield plate

Claims (4)

[Claims] 1. An outer race having an outer raceway on an inner peripheral surface, an inner racer having an inner raceway on an outer peripheral surface, and a plurality of rolling elements rotatably provided between the outer raceway and the inner raceway. ,
In a rolling bearing used in a state in which the outer ring is internally fitted to the housing and the inner ring is externally fitted to the shaft member, at least one of the surfaces of the outer ring that comes into contact with the surface of the housing. A rolling bearing characterized in that a coating made of a thermosetting synthetic resin is formed on a portion thereof. 2. The rolling bearing according to claim 1, wherein the thermosetting synthetic resin contains molybdenum disulfide. 3. A solvent in which a thermosetting synthetic resin is dissolved in at least a part of a surface of an outer ring that comes into contact with a surface of a housing for manufacturing the rolling bearing according to claim 1. And then applying heat to evaporate the solvent to form a thermosetting synthetic resin film on the portion, thereby producing a rolling bearing. 4. A housing, a shaft member, and, in order to rotatably support the shaft member with respect to the housing, an outer ring is internally fitted to the housing and the inner ring is externally fitted to the shaft member. A rolling machine device comprising a rolling bearing, wherein the housing is made of a material having a larger thermal expansion coefficient than the outer race, wherein the rolling bearing is the rolling bearing according to any one of claims 1 to 2. Rotary machinery characterized by things.