JP2002310169A - Rolling bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolling bearing having an improved lubrication property and guaranteed with a long service life under a severe environment without lubrication. SOLUTION: In this rolling bearing of the present invention 10, a plurality of rolling bodies 13 are inserted between an inner ring 11 and an outer ring 12, a spacer 14 is inserted between the rolling bodies 13 adjacent to each other, a clearance 14b is provided on the spacer 14 at a portion close to the rolling body 13, and a solid lubricant 15 is filled in the clearance 14b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling bearing in which a spacing member is interposed between adjacent balls of a non-separable ball bearing such as an angular ball bearing and a deep groove ball bearing, and more particularly, to rolling and sliding. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling bearing including a solid lubricant for lubricating a contact portion and having a spacing member that can contribute to extending the life of the bearing.

[0002]

2. Description of the Related Art In a non-separable type ball bearing, for example, an angular ball bearing, a plurality of rolling elements are arranged between an inner ring and an outer ring, and a spacing element is arranged between adjacent balls.
The spacer has a function of preventing the balls from falling off the inner and outer rings, preventing the balls from coming into contact with each other, and maintaining them at predetermined intervals. As such a spacing body, Japanese Utility Model Publication No. 5-14009 discloses a separator shown in FIG. This separator is composed of two metal cores 1 formed by processing a steel plate into a bowl shape.
Are placed on a mold of an injection molding machine in a state where the flat surfaces 13 of the bottom portions 11 are superimposed on each other.
The inner ring 14 is formed by injection molding a seat ring 15 made of synthetic resin on the inner circumference 14. The seat ring 15 has an X-shaped cross section in the radial direction passing through the center, and a recess 16 is formed at the center. Further, the side surface 17 of the seat ring portion 15 is in line contact with the ball 18 in a line or a small area. In such a separator, lubricating grease was stored in the recess 16 and an appropriate amount of grease could be supplied to the contact portion between the side surface 17 of the seat ring portion 15 and the ball 18, and good lubrication was obtained.

[0003]

However, a non-separable type ball bearing equipped with such a spacing member (separator) has a high temperature at which the evaporation of the lubricant is unavoidable, or an extreme loss at which the lubricant loses its viscosity. It may be used in a low temperature environment or in a special environment where an oil film is not formed due to low speed and high load. In such an environment, the lubricant sealed in a portion such as the recess 16 formed in the separator described above evaporates, loses viscosity, cannot form an oil film, and has a rolling surface or raceway surface of the bearing. May not go all the way to
It is difficult to use general lubricants or lubricants such as grease.

The present invention has been made in view of such a situation, and an object of the present invention is to provide a rolling bearing which can improve lubricity and can guarantee a long life in a severe non-lubricated environment.

[0005]

An object of the present invention is to provide a rolling bearing in which a plurality of rolling elements are inserted between an inner ring and an outer ring, and a spacing element is inserted between the rolling elements adjacent to each other. Rolling characterized by providing a space in a portion of the spacing body close to the rolling element, filling the space with a solid lubricant, and supplying a lubricant from the solid lubricant to the rolling element. Can be achieved by bearings. At this time, the rolling bearing is preferably of a non-separable type.

Here, the solid lubricant can be exemplified by, for example, a solid material composed of a polyolefin resin having affinity for lubrication and containing a large amount of lubricating oil. Further, the sintered metal member may be impregnated with a lubricant. The space preferably has a shape that opens in a portion of the spacer adjacent to the rolling element and forms a space inside the spacer, and a cylindrical shape can be exemplified, but the solid lubricant is not limited to this. Any shape may be used as long as the shape can be held.

[0007] According to such a rolling bearing, a space is provided in the spacer, and the space is filled with a solid lubricant. The lubricant contained in the solid lubricant is supplied to the rolling surface of the rolling element, or acts as a reinforcing lubricant or a substitute lubricant for grease previously filled in the bearing. Therefore, lubrication can be performed for a long time even in a severe environment without lubrication or in a water / dust environment. Further, the period of regular grease supply can be greatly extended.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. In the embodiments described below, the members and the like having the same configurations and operations as the members and the like already described are denoted by the same reference numerals or corresponding reference numerals in the drawings, and the description thereof will be simplified or omitted.

FIG. 1 is a partial sectional view of a non-separable angular contact ball bearing (hereinafter referred to as a bearing) 10 according to a first embodiment of the present invention. The bearing 10 shown in FIG. 1 has an inner raceway surface 11a on the outer peripheral surface.
, An outer race 12 having an outer raceway surface 12a on the inner peripheral surface, and an inner raceway surface 11a and an outer raceway surface 12
a and a plurality of balls 13 which are rotatably disposed as rolling elements between the plurality of balls 13 and, although not shown, are interposed between the plurality of balls 13 and described in detail below, and shown in FIG. It is roughly composed of a body. Track surface 1 of inner ring 11 and outer ring 12
The shape of both sides of 1a and 12a is such that one of them is the shoulder 1 of the load applying portion.
1b, 12b, and the other is formed by the thickness between the raceway diameter of the inner and outer rings 11, 12 and the opening end.
c and 12c. According to the present embodiment,
In the openings of the inner and outer rings 11, 12, no grooves are formed for balls and spacing bodies, and no holes are formed on the outer ring side. Also, the allowances 11c, 12c are the inner and outer rings 11, 12
May be provided so that the inner and outer rings cannot be separated.

FIG. 2 shows the II-I of the bearing 10 shown in FIG.
1 shows a sectional view. As shown in detail in FIG.
An interval member 14 is interposed between the plurality of balls 13 interposed between 1 and 12. The spacing member 14 is provided with a spherical seat 14a on both end surfaces (end surfaces in the left-right direction in the figure) of the side portion, and the surface (rolling surface) of the ball 13 is in line contact with the spherical seat 14a. Has made. The spherical seat 14a is
The ball 13 is formed in a concave curved surface corresponding to the outer shape, the vertical cross section is formed in a substantially arc shape, and a substantially central portion thereof is filled with a solid lubricant 15. Further, the spacing member 14 has a ball 13
Are formed slightly smaller than the diameter dimension of the inner and outer races 11a, 12a.
No contact with 12a.

FIG. 3 is a cross-sectional view of the above-described spacing member 14. FIG. 4A is a cross-sectional view of the spacer 14 not filled with the solid lubricant 15, and FIG. 4B is a cross-sectional view of the solid lubricant 15. In order to fill the solid lubricant 15 at the substantially center of the spherical seat 14a of the spacing member 14, the two spherical seats 1 are provided.
A through hole (vacancy) 14b penetrating the axis of 4a is provided. The size, shape, number, and the like of the through holes 14b are not particularly limited and are optional.
The opening end of the through hole 14b is narrower than the inside so that it does not detach even if it contracts by supplying the lubricant to the balls 13. Further, in order to make the entrance of the through hole 14b narrower than the inside thereof, the through hole 14b may be a tapered hole gradually narrowing from the back toward the entrance, or may be a hole which is narrowed down suddenly by narrowing the entrance. Examples of the solid lubricant 15 include a lubricant-containing polymer.

Here, the spacing member 14 itself is made of a thermoplastic synthetic resin, and is accurately formed by injection molding. As the synthetic resin, 6-nylon, 6,6-nylon, 4,6
Polyphenylene sulfide (PPS) resin and the like can be used, including polyamide resins such as -nylon and 12-nylon. These synthetic resins may contain a reinforcing material such as glass fiber, carbon fiber, potassium titanate whisker, or aluminum borate whisker in order to improve mechanical strength. The content of the reinforcing material is 50% by weight or less. If it exceeds this, the viscosity at the time of melting the resin will increase, and it will be difficult to mold with high accuracy.

Hereinafter, the material of the lubricant-containing polymer forming the solid lubricant 15 filled in the through hole 14b will be described in detail. Such a lubricant-containing polymer is used for a synthetic resin selected from the group of polyolefin-based resins having basically the same chemical structure such as polyethylene, polypropylene, polybutylene, and polymethylpentene, and a poly-α-olefin oil as a lubricant. Raw materials prepared by mixing any of paraffinic hydrocarbon oils, naphthenic hydrocarbon oils, mineral oils, ether oils such as dialkyldiphenyl ether oils, and ester oils such as phthalic acid esters, alone or in the form of a mixed oil. Is plasticized by heating above the melting point of the resin and solidified by cooling. The antioxidant, rust inhibitor, anti-wear agent, foam eraser, extreme pressure agent And the like.

The composition ratio of the above-mentioned lubricant-containing polymer is 10 to 50% by weight of the polyolefin resin and 90 to 50% by weight of the lubricant based on the total weight. 1 polyolefin resin
If the content is less than 0% by weight, a certain level of hardness and strength cannot be obtained, and it becomes difficult to maintain the initial shape when a load is applied due to rotation of the bearing, and the bearing is detached from the inner space of the bearing. The possibility of causing a defect is increased. On the other hand, when the amount of the polyolefin resin exceeds 50% by weight (that is, when the amount of the lubricant is less than 50% by weight), the supply of the lubricant to the bearing is reduced, and the life of the bearing is shortened.

The above synthetic resin groups have the same basic structure but different average molecular weights, ranging from 700 to 5 × 10 ⁶ . Among them, average molecular weight 700-1 × 1
0 ⁴ and those classified into wax (e.g., polyethylene wax) that, as a relatively low molecular weight an average molecular weight ^{l × l0 4 ~l × l0 6} , average molecular weight 1 × 10 ⁶ ~
Those having an ultrahigh molecular weight of 5 × 10 ⁶ are used alone or in combination as necessary. Combination of a relatively low molecular weight material and a lubricant provides some mechanical strength,
A lubricant-containing polymer having a lubricant supply capacity and an oil retaining property can be obtained.

Some of the relatively low molecular weight compounds are
When replaced with a wax, the difference in molecular weight between the wax and the lubricating oil is small, so that the affinity with the lubricating oil is high, and as a result, the oil retaining property of the lubricant-containing polymer is improved. Thus, the lubricant can be supplied for a long period of time. However, on the other hand, the mechanical strength decreases. As the wax, other than a polyolefin resin such as polyethylene wax, a hydrocarbon wax having a melting point in the range of 100 to 130 ° C. or more (for example, a paraffin synthetic wax) can be used.

On the other hand, when the lubricant is replaced with an ultrahigh molecular weight, the difference in molecular weight between the ultrahigh molecular weight and the lubricating oil is large, so that the affinity with the lubricating oil is lowered, and as a result, the oil retention is reduced. The bleeding of the lubricant from the lubricant-containing polymer is accelerated. As a result, the time required to reach the amount of lubricant that can be supplied from the lubricant-containing polymer is shortened, and the life of the bearing is shortened. However, the mechanical strength is improved.

Considering the balance of moldability, mechanical strength, oil retention and lubricant supply, the composition ratio of the lubricant-containing polymer is 0 to 5% by weight, classified as wax, and relatively low molecular weight. 8 to 48% by weight, ultra high molecular weight 2-1
It is preferable to use 5% by weight and a total of 10 to 50% by weight of the three resin components (the remainder being 90 to 50% by weight of the lubricant).

As one of the mechanical strengths, the hardness [HDA] of the lubricant-containing polymer of the present invention is preferably 65 or more, more preferably 70 or more. Hardness [HD
A] is less than 65, the bearing is weak in strength (rolling element)
There is a risk of damage due to rotation.

In order to improve the mechanical strength of the lubricant-containing polymer of the present invention, the following thermoplastic resin and thermosetting resin may be added to the above-mentioned polyolefin resin.

As the thermoplastic resin, various resins such as polyamide, polycarbonate, polybutylene terephthalate, polyphenylene sulfide, polyether sulfone, polyether ether ketone, polyamide imide, polystyrene and ABS resin can be used.

As the thermosetting resin, resins such as unsaturated polyester resin, urea resin, melanin resin, phenol resin, polyimide resin and epoxy resin can be used.

These resins may be used alone or as a mixture. Further, in order to disperse the polyolefin resin and the other resin in a more uniform state, a suitable compatibilizer may be added as necessary.

In order to improve the mechanical strength, a filler may be added. For example, inorganic whiskers such as calcium carbonate, magnesium carbonate, potassium titanate whiskers and aluminum borate whiskers, or inorganic fibers such as glass fibers and metal fibers, and braided cloths thereof may be added. For organic compounds, carbon black, graphite powder, carbon fiber, aramid fiber, polyester fiber and the like may be added.

Further, in order to prevent deterioration of the polyolefin resin due to heat, N, N'-diphenyl-P-phenyldiamine, 2,2'-methylenebis (4-ethyl-
Antioxidants such as 6-t-butylphenol), and 2-hydroxy-4-n-octoxybensophenone, 2- (2′-hydroxy-3) for the purpose of preventing deterioration due to light.
An ultraviolet absorber such as'-t-butyl-5'-methyl-phenyl) -5-chlorobenzotriazole may be added.

The addition amount of all the additives (other than the polyolefin resin and the lubricant) should be 20% by weight or less based on the total amount of the molding raw material as a whole in order to maintain the lubricant supply capability. Is preferred.

As the material of the lubricant-containing polymer that can be used in the present invention, in addition to those based on the polyolefin resin described above, any thermoplastic resin that can be injection-molded can be used. For example, polyester elastomers can be used to increase the oil content. In addition to the thermoplastic resin, a thermosetting resin such as polyurethane and polyurea elastomer can be used. In the case of polyurethane, a grease is used as a lubricant, a urethane prepolymer containing an isocyanate group, which is a reaction raw material, and an amine-based curing agent are uniformly mixed with the grease, and then the two mixtures are further mixed to obtain a desired shape. And if necessary, heated to react, and cured with grease contained. In the case of polyurea, an amine component consisting of a mixture of an aromatic polyamine compound and an aromatic diamine containing a soft segment in the molecular chain is uniformly mixed with a lubricating oil compatible therewith or a grease based on the lubricating oil. The resulting mixture is further mixed with a polyisocyanate component, mixed, filled into a mold having a desired shape, heated and reacted as needed, and cured while containing a lubricant.

As a method of filling the solid lubricant 15 into the through-holes 14b provided in the spacing member 14, a solid lubricant 15 before curing (solidification) is filled into the through-holes 14b, and then the outer shape of the spacing member 14 is maintained. In a mold that heats (when the base resin is a thermoplastic resin, the melting point or higher; when the base resin is a thermosetting resin, the curing temperature), and then cools (solidifies) as necessary.
There is heat molding to be performed. When the base resin of the solid lubricant 15 is a thermoplastic resin, the solid lubricant 15 can also be formed by injection molding (insert molding) using the spacer 14 as a core.

Further, as the solid lubricant 15, a sintered alloy obtained by adding a lubricant to a metal powder and performing a sintering process can be employed. Since the solid lubricant 15 is formed of metal, the strength of the spacer 14 can be improved,
An impregnated lubricant can be supplied. Note that, as the metal powder, molybdenum disulfide can be exemplified.

According to the bearing 10 having the above-described structure, the solid lubricant 15 impregnated with the lubricating oil is filled in the through hole 14b provided in the spacer 14, and the lubricant oozing out of the solid lubricant 15 is removed. It is supplied to the rolling surface of the ball 13. Therefore, lubrication can be performed for a long time even in a severe environment without lubrication or in a water / dust environment. Further, the period of regular grease supply can be greatly extended. further,
According to such a configuration of the present embodiment, the lubricating oil oozing out of the solid lubricant 15 filled in the space 14
Since the bearing 10 is lubricated, it is particularly suitable for a bearing used under a low-speed and high-load environment such as a non-separable angular ball bearing and a non-separable cross roller bearing.

The present invention is not limited to the above-described embodiment, and appropriate modifications and improvements can be made. In the present embodiment, a non-separable angular ball bearing employing balls as rolling elements has been exemplified. However, the configuration of the present invention may be applied to a non-separable cross roller bearing or the like.

[0032]

As described above, according to the rolling bearing of the present invention, the lubricating property is improved, and a long life of the bearing can be guaranteed in a severe environment without lubrication.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of an angular ball bearing 10 showing a first embodiment of the present invention.

FIG. 2 is a sectional view of the angular ball bearing 10 shown in FIG.
It is I sectional drawing.

FIG. 3 is a cross-sectional view of a spacer 14 filled with a solid lubricant 15;

FIG. 4 is a sectional view of a spacer 14 and a solid lubricant 15;

FIG. 5 is a cross-sectional view of a separator conventionally used as a spacer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Non-separable angular ball bearing (rolling bearing) 11 Inner ring 11a Inner ring raceway surface 12 Outer ring 12a Outer ring raceway surface 13 Ball (rolling element) 14 Spacer 14a Spherical seat 14b Through hole (vacant space) 15 Solid lubricant

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) C10M 107/02 C10M 107/02 143/02 143/02 143/04 143/04 143/06 143/06 143 / 08 143/08 169/04 169/04 F16C 19/16 F16C 19/16 19/20 19/20 33/372 33/372 // C10N 40:02 C10N 40:02 F term (reference) 3J101 AA02 AA26 AA33 AA42 AA54 AA62 BA13 BA16 BA20 CA14 DA14 EA31 EA36 EA47 EA55 EA76 FA32 4H104 BA02A BA07A BB08A BB23A CA01A CA02C CA03C CA04C CA05C DA02A PA01 QA21

Claims (1)

[Claims] 1. A rolling bearing in which a plurality of rolling elements are inserted between an inner ring and an outer ring, and a spacing element is inserted between the rolling elements adjacent to each other, wherein a portion of the spacing element adjacent to the rolling element. A rolling bearing, wherein a solid lubricant is filled in the space, and a lubricant is supplied from the solid lubricant to the rolling elements.