JP2012036940A - Roller and cage assembly, roller bearing and cage assembly, and cage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a roller and cage assembly, and a bearing employing the roller and cage assembly exhibiting such properties that a film formed by surface treatment causes no increase in stress and is not peeled off from the cage even if the film is thick, surface treatment is not affected by an additive included in oil for use, the wear of the cage can be prevented when the cage is used in an engine with large displacement or the like, and adhesiveness between the surface treatment layer and a substrate is improved.SOLUTION: The cage 2 is plated to form a primary plated layer 4 on the surface, and further plated to form a plated multilayer 5 comprising a plurality of plated layers on the surface of the primary plated layer 4. The plated multilayer 5 has a Ni PTFE plated layer formed on the surface of the primary plated layer 4, another plated layer which is formed on the surface of the Ni PTFE plated layer and has the same plating as that of the primary plated layer 4, and a Ni PTFE plated layer formed on the surface of the another plated layer.

Description

  The present invention relates to a roller with a cage, a roller bearing with a cage, and a cage used in, for example, a support structure for a crankshaft and a connecting rod support structure for a four-wheeled vehicle, a two-wheeled vehicle, and a general-purpose engine. And a technique for solving poor lubrication.

A roller with a cage is composed of a roller and a cage, and has a structure in which the outer peripheral surface of the roller is in line contact with the raceway surfaces of the inner ring and the outer ring. For this reason, it has the advantage that high load capacity and high rigidity can be obtained for a small bearing projected area. Accordingly, the roller with cage is widely used in various fields including automobiles.
Generally, a roller with a cage of a sliding bearing or a rolling bearing is used for a large and small end of a two-wheeled vehicle. In the case of a two-cycle engine, the large and small ends are lubricated by a spray-like mixed liquid in which gasoline and engine oil are mixed. Accordingly, rolling bearings such as rollers with cages and shell radial bearings are used for sliding bearings because wear and lubrication failure occur. However, in the rolling bearings used, the rollers with cages used copper plating or silver plating in order to prevent the outer diameter and width of the cage from being worn and poor lubrication.
For high-speed rotation that cannot be tolerated by copper plating or silver plating, composite plating in which the base material is nickel as a main material and fine particles of fluororesin are uniformly dispersed and co-deposited has been proposed (Patent Document 1). This device is a countermeasure content from the viewpoint of preventing wear and poor lubrication under high-speed use conditions.

  Therefore, the applicant of the present application newly applied for Japanese Patent Application No. 2009-120894. In the invention according to this application, a base plating layer is applied to the surface of the cage, a Ni / PTFE plating layer is applied to the surface of the base plating layer, and the total film thickness of the base plating layer and the Ni / PTFE plating layer is specified. Technology. In addition, as a cage that is lightweight, compact, large in strength, and excellent in flexibility, heat resistance, and oil resistance, a multilayer film is provided on the surface of the cage so that adjacent layers are made of different metals or alloys. Techniques have been proposed (Patent Document 2).

Utility Model Registration No. 2582402 JP 2007-120734 A

  In Patent Document 1, a composite plating containing nickel as a main material and containing a fluororesin is formed on a cage for the purpose of preventing wear and lubrication failure with respect to high speed. However, the wear of copper and silver plating in recent years is not severe in use conditions, but the plating dissolves (disappears) due to a chemical reaction due to the influence of lubricating oil, and the cage may cause poor lubrication. In particular, it often occurs in bearings used in 4-cycle engines.

In the case of a four-cycle engine, gasoline and engine oil are not mixed, and the engine oil can be directly supplied to the large and small ends. For this reason, a low-priced plain bearing having a higher load capacity than a rolling bearing is used, and the rolling bearing is hardly used.
However, in recent years, a sliding bearing (a roller with a cage) has been replaced with a sliding bearing of a support portion (for example, a connecting rod large end) of a four-cycle engine in order to improve engine fuel efficiency. The application of rolling bearings to this four-cycle engine is the beginning of the problem.

  By the way, the oil to be used is different between the 2-cycle engine and the 4-cycle engine. In a 4-cycle engine, oil in the oil pan is pumped to lubricate each part of the engine. After that, the oil returns to the oil pan again. On the other hand, in a two-cycle engine, oil is mixed with fuel and adhered to a rotating part or the like, or each part of the engine is lubricated by pumping from an oil tank, and then enters the combustion chamber and burns with the mixture. The performance required for the two-cycle engine oil and the four-cycle engine oil is greatly different due to the difference in the structure such as the difference in the lubrication mechanism and the valve mechanism.

  The major difference in the composition of these two-cycle engine oil and four-cycle engine oil is the presence or absence of sulfated ash and zinc dialkyldithiodiphosphate (ZnDTP). The low sulfated ash content in the two-cycle engine oil is that the acid neutralization performance of the overbased detergent, which is the main factor of the ash content, is not required, and the ash content increases the combustion chamber deposits and can cause plug misfire. Because there is. The reason why ZnDTP is not prescribed for the two-cycle engine oil is that the two-cycle engine does not require anti-oxidation property of the oil, and because there is no valve mechanism, severe wear prevention performance is not required. It is said that ZnDTP is usually pyrolyzed at 150 to 200 ° C, but there is a report that the temperature around the piston and ring during high load operation exceeds 200 ° C. , Causing ring sticking. In order to prevent this piston contamination and ring sticking, a large amount of detergent is required, which is why ZnDTP is not added. The ZnDTP has antioxidation ability, corrosion prevention ability, load bearing performance, wear prevention ability and the like, and is widely used in engine oil and industrial lubricating oil as a so-called multifunctional additive.

As a wear prevention mechanism of ZnDTP,
(1) Sulfur and phosphorus in ZnDTP react with metals to form iron sulfide and phosphate films to prevent wear.
(2) ZnDTP decomposes to form a polyphosphate film on the metal surface to prevent wear.
The theory is powerful.
As described above, the 4-cycle engine oil contains ZnDTP, which is an additive, and sulfur is contained in the components in this ZnDTP. As a wear prevention mechanism, this sulfur reacts with metals to form a film and has a wear prevention effect, but it has been found from various evaluations that copper plating and silver plating applied to the cage are counterproductive.

  In other words, when a cage plated with copper or silver is immersed in high-temperature four-cycle engine oil, it turns out that the chemical components of copper and silver increase in the oil over time, and it dissolves in the oil. It was approved. Further, the silver plating changed to black, and the plating became brittle and was easily peeled off. Furthermore, plating peeling of a part of the cage that does not come into contact with other parts may be recognized. It was very expensive to prevent these platings from peeling off. Therefore, a surface treatment that is not affected by the additive contained in the engine oil is necessary. Moreover, it is necessary to prevent peeling of plating by improving the adhesion with the base material (retainer).

Even in the surface treatment according to the above-mentioned application of the present applicant, it has been found that the surface-treated film is worn by an engine having a large displacement. Therefore, an attempt was made to increase the film thickness of the surface treatment. However, it was found that with the same type of surface treatment, when the film thickness is increased, the internal film stress increases and the film easily peels off. Enormous costs have been incurred to make it difficult to remove the surface-treated film.
In the technology of Patent Document 2, there is no base plating layer between the cage surface and the multilayer film, and the total film thickness of the multilayer film is very thin, on the order of nm. There is a concern that the surface of the cage may wear due to wear.

  The purpose of the present invention is to prevent the surface treatment from increasing the film stress even if the film thickness is large, and to prevent the film from being peeled off from the cage, and to make the surface treatment unaffected by the additive contained in the oil used. Furthermore, when the cage is used in a large displacement engine or the like, the cage can be prevented from wearing and lubrication failure, and the adhesion between the surface treatment layer and the substrate is improved. It is providing a bearing using a roller with a cage and a roller with a cage.

  The roller with cage according to the present invention is the roller with cage having a plurality of rollers and a ring-shaped cage having pockets respectively holding the rollers at a plurality of locations in the circumferential direction. An undercoat plating layer is applied to the surface of the Ni, PTFE plating layer containing nickel and PTFE on the surface of the undercoat plating layer, and the same plating as the undercoat plating layer is applied to the surface of the Ni · PTFE plating layer. And a multilayer plating layer comprising a plurality of plating layers having a nickel / PTFE plating layer containing nickel and PTFE applied to the surface of the plating layer.

According to the above configuration, since the laminated plating layer composed of a plurality of plating layers is applied to the surface of the base plating layer, the plating layer can be formed even if the film thickness, that is, the total thickness of the plating layer is increased under severe use environment. It will not peel off. In other words, since a multilayer plating layer composed of a plurality of plating layers is applied to the surface of the underlying plating layer, even if the total thickness of the plating layer is large, the film stress of the surface treatment does not increase, and the plating layer is peeled off. This can be prevented. Furthermore, since the film thickness of the laminated plating layer can be increased, the surface treatment remains even after long-term operation, and the wear and lubrication failure of the cage can be prevented.
A plurality of types of samples according to the present invention and samples with a two-layered plating layer according to the prior art are manufactured, and the so-called ring-on-disk type tester is used for the adhesion of plating of these samples, that is, the wear resistance. Was used to evaluate. The total film thickness of the plating layer in the sample of the present invention is larger than the total film thickness of the plating layer in the sample according to the prior art.
According to the test results, in the sample of the present invention, although the surface layer of the laminated plating layer was worn, no metal was generated. Moreover, peeling of the plating layer was not recognized. On the other hand, in the samples according to the prior art, those in which the plating layer was gradually worn and metal was generated, and those in which the plating layer was partially peeled off with the wear of the plating layer were observed.

The laminated plating layer includes a nickel / PTFE plating layer containing nickel and PTFE applied to the surface of the base plating layer, and the same plating as the base plating layer applied to the surface of the Ni / PTFE plating layer. And a Ni / PTFE plating layer containing nickel and PTFE applied to the surface of the plating layer.
The “PTFE” is an abbreviation for polytetrafluoroethylene, which is a polymer of tetrafluoroethylene, which is a fluorocarbon resin composed of only fluorine atoms and carbon atoms. This fluorocarbon resin shape is a polygonal shape.

  According to this configuration, nickel in the Ni · PTFE plating layer has a property that it is difficult to react with the additive as compared with copper and silver, so that elution can be suppressed. It was confirmed by immersion test that nickel, which is a metal component of the Ni / PTFE plating layer, does not dissolve under the high temperature condition of the 4-cycle engine oil. Even if 200 hours passed as the immersion time, the Ni / PTFE plating layer And no element related to the underlying plating layer was detected. Furthermore, the self-lubricating action of PTFE in the Ni / PTFE plating layer reduces the friction coefficient of plating and improves the wear resistance.

The PTFE in each of the Ni / PTFE plating layers may be one in which PTFE particles are dispersed during nickel plating.
In the laminated plating layer, the plating layer made of the same plating as the base plating layer and the base plating layer may be a nickel plating layer. Since this nickel plating layer and each Ni / PTFE plating layer contain a common composition, that is, nickel, the composition in the vicinity of both layers gradually changes, and there is no gap between the nickel plating layer and the Ni / PTFE plating layer. It can be adhered. Therefore, the adhesiveness is excellent over the base material, the nickel plating layer, the Ni / PTFE plating layer, and the nickel plating layer.

The plating layer may have a thickness of 3 μm to 10 μm, and the Ni / PTFE plating layer may have a thickness of 5 μm to 15 μm.
The base plating layer forms an anchor effect between the Ni / PTFE plating layer and the base material, and the plating layer is a plating layer that forms an anchor effect between the Ni / PTFE plating layers. The following thin film thickness is sufficient.

The PTFE amount in the Ni / PTFE plating layer may be a different PTFE amount for each Ni / PTFE plating layer. Thus, by changing the amount of PTFE, a laminated plating layer having better adhesion can be obtained.
The base plating layer may be a plating layer that does not include PTFE, and the outermost layer of the laminated plating layer may be a plating layer that includes PTFE. Thus, when the outermost layer is a plated layer containing PTFE, the sliding resistance can be effectively reduced for the self-lubricating performance of PTFE.

Each plating layer in the laminated plating layer may have a different film thickness for each plating layer.
The laminated plating layer may be composed of three or more plating layers.
In these cases, in this case, the total thickness of the plating layer can be increased, and there is a life extension effect against wear.

A roller bearing with a cage according to the present invention includes any one of the rollers with a cage according to the present invention and a bearing ring on which the plurality of rollers roll.
The cage of the present invention is a cage in a roller with a cage comprising a plurality of rollers and ring-shaped cages each having a pocket for holding each of the rollers at a plurality of locations in the circumferential direction, A base plating layer is applied to the surface of the cage, and a multilayer plating layer composed of a plurality of plating layers is applied to the surface of the base plating layer.

  You may apply the connecting rod large end bearing of the engine using the said roller with a retainer of this invention.

  The roller with cage according to the present invention is the roller with cage having a plurality of rollers and a ring-shaped cage having pockets respectively holding the rollers at a plurality of locations in the circumferential direction. An undercoat plating layer is applied to the surface of the Ni, PTFE plating layer containing nickel and PTFE, and the same plating as the undercoat plating layer is applied to the surface of the Ni · PTFE plating layer. And a multilayer plating layer comprising a plurality of plating layers having a nickel / PTFE plating layer containing nickel and PTFE applied to the surface of the plating layer. For this reason, even if the film thickness is thick, the film stress of the surface treatment does not increase, and the film, that is, the base plating layer and the laminated plating layer do not peel from the cage. Further, the surface treatment can be performed without being affected by the additive contained in the oil used. Further, when the cage is used in a large displacement engine or the like, wear and lubrication failure of the cage can be prevented, and adhesion between the film and the substrate can be improved.

(A) is sectional drawing of the roller with a retainer which concerns on 1st Embodiment of this invention, (B) is a principal part top view of the retainer. It is principal part sectional drawing of the laminated plating layer of the roller with the same holder | retainer. (A) is sectional drawing of the testing machine which evaluates the abrasion resistance of plating of the roller with the cage, (B) is an expanded sectional view of the principal part of the testing machine. It is a figure showing the relationship between immersion time and the amount of detected elements. It is a figure which shows the relationship between the surface roughness and wear amount of a Ni * PTFE plating layer. It is a figure showing the relationship between the plating hardness after quenching of a Ni * PTFE plating layer, and the amount of wear. 1 is a cross-sectional view of a roller bearing with a cage according to an embodiment of the present invention. (A) Sectional drawing of the roller with a retainer which concerns on other embodiment of this invention, (B) is the sectional view on the AA line of FIG. 8 (A). It is principal part sectional drawing of the bearing for connecting rod big ends of the engine using the roller with the said holder | retainer.

An embodiment of the present invention will be described with reference to FIGS. The roller with cage according to the embodiment of the present invention is used in, for example, a support structure for a crankshaft and a connecting rod support structure for a four-wheeled vehicle, a two-wheeled vehicle, and a general-purpose engine. However, the present invention is not limited to the crankshaft support structure and the connecting rod support structure.
As shown in FIG. 1A, the roller with cage 50 includes a plurality of rollers 1 and a cage 2. There is no inner ring, and the roller 1 is in rolling contact with the outer peripheral surface of the shaft supported by the roller 50 with cage. For example, a needle roller is used as the roller 1, and the end surface 1a of the roller 1 is a flat surface. As shown in FIG. 1B, the cage 2 has a ring shape having pockets 3 for holding the rollers 1 at a plurality of locations in the circumferential direction. As shown in FIGS. 1A and 2, a base plating layer 4 is applied to the surface of the cage 2, and a laminated plating layer 5 (described later) is applied to the surface of the base plating layer 4. . In FIG. 1 (A), the laminated plating layer 5 is shown with the thickness of the plating layer emphasized from the actual one.

  As shown in FIG. 1 (A), the cage 2 is formed of a turned product from a cylindrical material, for example. In another construction method, it consists of a press-formed product from a thin steel plate material. The cage 2 is formed in a substantially cylindrical shape having a pair of flange portions 6, 6 that are annular portions projecting to the inner diameter side at both ends, and the axial central portion of the peripheral wall is formed as a small diameter portion 7 radially inward. Yes. As shown in FIG. 1 (B), the retainer 2 has a plurality of circumferential column portions 8 that connect a pair of flange portions 6 and 6, and the space between adjacent column portions 8 and 8 is the pocket 3. It becomes. The cage 2 may have an annular portion such as a flat shape instead of the flange portions 6 and 6.

  As shown in FIG. 1 (B), on the peripheral edge of the opening of the pocket 3 in the column portion 8, a falling edge 9 for preventing the roller 1 from falling off is formed on the small diameter portion 7 in the center in the axial direction. Protrusions 10 and 10 for preventing the rollers 1 from falling off are formed in the diameter portion. An inclined edge 11 for guiding the roller 1 in the circumferential direction is formed between the protruding edges 9 and 10 for preventing the dropout at the peripheral edge of the opening of the pocket 3 in the column portion 8. The inclined edge 11 is inclined inward from the radially outer side toward the central portion in the axial direction. The rollers 1 are prevented from slipping in and out by the falling-off preventing protrusions 9 and 10 and guided in the circumferential direction by the inclined edges 11.

The laminated plating layer 5 will be described.
As shown in FIGS. 1A and 2, a base plating layer 4 is applied to the surface of the cage 2, and a laminated plating layer 5 is applied to the surface of the base plating layer 4. The laminated plating layer 5 is composed of a plurality of plating layers. The base plating layer 4 is a nickel plating layer. The surface to be plated is the cage surface, and includes the width surface, inner diameter surface, and pocket of the cage.
In this example, as shown in FIG. 2, the laminated plating layer 5 includes a Ni / PTFE plating layer 5a containing nickel and PTFE, and the Ni / PTFE plating layer 5a. A plating layer 5b made of the same plating as that of the base plating layer 4 (ie, nickel plating) and a Ni / PTFE plating layer 5c containing nickel and PTFE applied to the surface of the plating layer 5b. Have. In other words, in this example, the first base plating layer 4, the second Ni / PTFE plating layer 5 a, the third plating layer 5 b, and the fourth layer are sequentially formed on the surface of the cage 2 that is the base material. Ni / PTFE plating layer 5c is applied.

As shown in FIG. 2, PTFE in each of the Ni / PTFE plating layers 5a and 5c is obtained by dispersing and eutecting PTFE fine particles (indicated by black dots in the figure) in a base material mainly composed of nickel. is there. The amount of PTFE in each of the Ni / PTFE plating layers 5a and 5c is defined as 1 vol% or more and 35 vol% or less. When the amount of PTFE is small, the wear coefficient is high and the sliding characteristics are inferior, and the amount of plating wear tends to be large. On the contrary, when the amount of PTFE is too large, the hardness after heat treatment is low, so that the amount of wear tends to increase. Further, when a large amount of PTFE is contained, the cost increases.
In this embodiment, by defining the PTFE amount of each of the Ni / PTFE plating layers 5a and 5c as 1 vol% or more and 35 vol% or less, the friction coefficient is low, the sliding characteristics are excellent, and the plating wear amount can be reduced. Further, it becomes possible to reduce the manufacturing cost.

The film thicknesses δ1 and δ3 of the first base plating layer 4 and the third plating layer 5b are 3 μm or more and 10 μm or less, respectively, and the film thicknesses δ2 of the second and fourth Ni / PTFE plating layers 5a and 5c. , Δ4 are 5 μm or more and 15 μm or less, respectively.
The first base plating layer 4 forms an anchor effect between the Ni / PTFE plating layer 5a and the substrate, and the third plating layer 5b forms an anchor effect between the Ni / PTFE plating layers 5a and 5c. It is a plating layer.
Further, when the adhesion of the plating, that is, the wear resistance, was evaluated using the following ring-on-disk type tester, the film thicknesses δ2, δ4 of the second and fourth Ni / PTFE plating layers 5a, 5c were evaluated. When the thickness is 5 μm or more and 15 μm or less, the total film thickness δt of the plating layer can be increased, and there is an effect of extending the life against wear.

The adhesion (abrasion resistance) of the laminated plating layer 5 will be described with reference to Table 1 and FIG.

  As shown in Table 1, five types of samples (No. A to E) were manufactured, and the adhesion of plating was evaluated using a ring-on-disk type tester. In Table 1, samples A and B are samples having a two-layer structure according to the prior art in which no plating layer is provided on the third layer and the fourth layer, respectively. Samples C, D, and E are samples each provided with a laminated plating layer according to the embodiment of the present invention. The unit of numerical values in the table is μm.

As shown in FIG. 3A, the ring-on-disk type testing machine RM includes a rotating shaft 30 that is rotationally driven, and a circle that is fixed to the upper end of the rotating shaft 30 via a fixture 31 such as a bolt. It has a plate-like mating member 32, a load shaft 33 arranged concentrically facing the surface portion of the mating member 32, and a metal ring member 34 attached to the lower end portion of the load shaft 33.
In this example, as shown in FIG. 3B, the rotating shaft 30 is rotated while pressing each sample provided on the lower end surface 34 a of the ring member 34 against the surface portion of the counterpart material 32. This confirms the presence or absence of wear and peeling of the plating layer in each sample. The counterpart material 32 is made of, for example, SUJ2, and a material obtained by polishing the surface portion of the counterpart material 32 is used.

According to the test results, in Samples C, D, and E, the surface layer of the laminated plating layer 5 was worn, but no metal was generated and the plating layer was not peeled off. On the other hand, in the sample A according to the prior art, the first layer and the second layer were gradually worn and bare metal was generated. In sample B according to the prior art, the second layer was worn and peeling of the second layer was observed.
As described above, in the samples C, D, and E of the present invention, the plating layer does not peel off even when the total thickness δt of the plating layer is increased in a severe use environment. In other words, even if the total thickness δt of the plating layer is large, the film stress of the surface treatment does not increase, and the plating layer can be prevented from peeling off. Furthermore, since the film thickness of the laminated plating layer 5 can be increased, the surface treatment remains even after long-term operation, and wear and lubrication failure of the cage 2 can be prevented.

About the adhesion strength of the plating with and without the underlying plating layer The cage 2 according to this embodiment is provided with a nickel plating layer as the underlying plating layer 4 in order to improve the adhesion strength of the plating. The adhesion force due to the presence or absence of the underlying plating layer 4 was compared using the actual roller with cage (inner diameter 28 mm × outer diameter 34 mm × width 17 mm) in the same crank motion motion as the actual machine. The results are shown in Table 2.

  As shown in Table 2, the product without the base plating layer 4 was found to wear and peel off the plating layer after the test. On the other hand, although the product which gave the base plating layer 4 showed slight abrasion after the test, peeling of the plating layer was not recognized. Thus, it has been found that the base treatment is necessary to improve the adhesion of the plating.

The dissolution of the surface treatment will be described.
It was confirmed by an immersion test that the metal components and the like of the Ni / PTFE plating layers 5a and 5c according to the embodiment of the present invention do not dissolve under the high temperature conditions of the 4-cycle engine oil. As shown in FIG. 4, in the conventional copper plating and silver plating, a large amount of element is detected from the oil as the immersion time elapses. In the figure, copper plating is indicated by square marks, and silver plating is indicated by triangle marks.
On the other hand, in the same figure, the one having the Ni / PTFE plating layer according to the embodiment represented by rhombus, even if the immersion time is 200 hours, the base plating layer, the Ni / PTFE plating layer, the nickel plating layer, And the elements related to the Ni · PTFE plating layer were not detected.

The standard value of the surface roughness of the Ni / PTFE plating layer 5c will be described.
In the embodiment of the present invention, the surface roughness of the Ni · PTFE plating layer 5c which is the outermost layer is set to Ra 0.7 μm or less.
“Ra” is a center line average roughness Ra defined by Japanese Industrial Standards, and is JIS 0601.
-Measured according to 1976 surface roughness standard.
In order to confirm whether or not the wear amount of the plating itself changes depending on the surface roughness of the Ni / PTFE plating layer 5c, the wear comparison evaluation was performed using the roller with cage and the test conditions for which the film thickness was evaluated. . As a result, as shown in FIG. 5, when the surface roughness exceeds Ra 0.7 μm, the amount of wear tends to increase. This is a result that the roughness of the roughness itself is higher and the surface roughness is easier to wear.

The hardness of the Ni · PTFE plating layers 5a and 5c will be described.
In the embodiment of the present invention, the Ni / PTFE plating layers 5a and 5c are cured by heat treatment, and the plating hardness after the heat treatment of the Ni / PTFE plating layers 5a and 5c is set to Hv300 or more and Hv700 or less.
In order to determine the optimum value of the plating hardness of the Ni / PTFE plating layers 5a and 5c, wear comparison was performed under the same test conditions using the same roller with cage as when the total film thickness δt was determined. The plating hardness is a value determined by the PTFE content and the quenching temperature in the Ni / PTFE plating layers 5a and 5c. Therefore, the test sample was manufactured by changing the quenching temperature while keeping the PTFE content constant.

  As shown in FIG. 6, if the plating hardness after quenching of the Ni / PTFE plating layers 5a and 5c is Hv300 or more and Hv700 or less, the difference in wear amount is within 0.001 mm, and no difference is recognized. It was a result. When the plating hardness after quenching of the Ni · PTFE plating layers 5a and 5c is less than Hv300, the amount of wear increases. If it exceeds Hv700, the hardness is too high and the plating layer may crack.

According to the roller 50 with a cage described above, the base plating layer 4 is applied to the surface of the cage 2, and the surface of the base plating layer 4 is provided with the laminated plating layer 5 composed of a plurality of plating layers. Even if the total film thickness δt of the layer is large, the film stress of the surface treatment does not increase, and peeling of the plating layer can be prevented. Furthermore, since the film thickness of the laminated plating layer 5 can be increased, the surface treatment remains even after long-term operation, and wear and lubrication failure of the cage 2 can be prevented.
Of the multi-layer plating layer 5, nickel in the Ni / PTFE plating layers 5a and 5c is less likely to react with additives than copper and silver, so that elution can be suppressed as shown in FIG. It becomes. Therefore, when this roller 50 with a retainer is used in a four-cycle engine, even if the roller 50 with a retainer is immersed in this engine oil, it can be suppressed that nickel is eluted in the engine oil. Therefore, it is possible to prevent the laminated plating layer 5 from becoming brittle, thereby preventing plating peeling. Even if an additive is contained in the engine oil, nickel is not eluted into the engine oil without being affected by the additive, thereby preventing the laminated plating layer 5 from becoming brittle. And plating peeling can be prevented.

Also, the base plating layer 4 of the first layer is a nickel plating layer, and this nickel plating layer is provided between the Ni / PTFE plating layer 5a of the second layer and the base material (cage), so that the base material and the Ni. The adhesion strength with the PTFE plating layer 5a is improved, and plating peeling is prevented. In other words, since the first layer and the second layer contain a common composition, that is, nickel, the composition in the vicinity of both layers gradually changes, and the interface between the nickel plating layer and the Ni / PTFE plating layer 5a is brought into close contact with no gap. be able to. Therefore, the adhesiveness is excellent over the base material, the nickel plating layer, and the Ni / PTFE plating 5a layer. As described above, the adhesion is improved because the bonding between the metals is strengthened by providing a plating having a similar composition between them.
The third plating layer 5b is a nickel plating layer, and the nickel plating layer is interposed between the second and fourth Ni / PTFE plating layers 5a and 5c, thereby allowing the first and second layers to be interposed. Similarly, the adhesion strength between the second layer and the third layer is improved, and the adhesion strength between the third layer and the fourth layer is improved, thereby preventing plating peeling.
Further, the self-lubricating action of PTFE in the Ni / PTFE plating layer 5c reduces the friction coefficient of plating and improves the wear resistance.

When the base plating layer 4 and the laminated plating layer 5 are applied to the cage, a plating layer is attached to the roller guide surface of the cage pocket 3, so that the wear of the roller 1 can be reduced. Further, since there is no need to mask a part of the cage 2 or to remove the adhered plating layer, it is possible to reduce the man-hour of the entire plating operation.
The laminated plating layer 5 is applied to the surface of the fourth Ni / PTFE plating layer 5c and includes a plating layer (fifth layer) made of the same plating as the base plating layer 4 (that is, nickel plating). Also good.
The base plating layer 4 and the laminated plating layer 5 may be applied to the entire surface of the cage, or may be applied only to necessary portions such as the outer diameter surface and the width surface of the cage.

  FIG. 7 shows a roller bearing with a cage according to an embodiment of the present invention. This roller bearing with cage is composed of the roller with cage 50 (50A) having any one of the above-described configurations and the race ring 14 with which the plurality of rollers 1 are in rolling contact. In this example, the outer ring is used as the race ring 14. The roller bearing with a cage may be configured to include one or both of the outer ring and the inner ring (or shaft Sh).

  A roller 50B with a retainer in FIG. 8 includes a plurality of rollers 1 and first and second retainers 2C and 15. FIG. 8A is a cross-sectional view of a roller with a cage cut along a plane including the axis L1. FIG. 8B is a cross-sectional view taken along line AA in FIG. The first cage 2C has the same configuration as the cage 2 of the first embodiment described above with reference to FIGS. A base plating layer 4 and a laminated plating layer 5 are provided on the surface of the first cage 2C. The second retainer 15 is a ring-shaped member having a flat surface, and a pocket 15a for retaining the roller 1 is formed. The surface of the second cage 15 is also provided with a base plating layer 4 and a laminated plating layer 5. The second cage 15 is disposed on the inner peripheral surface of the flange portion 6 of the first cage 2C via a radial gap.

  FIG. 9 is a cross-sectional view of the main part of a connecting rod large end bearing for an engine using rollers with cages. Any one of the rollers with cage 50 according to the present invention is applied to the crankshaft support bearings BR1 and BR1, the bearing BR2 of the connecting portion 35 between the connecting rod CR and the crankshaft CS, that is, the connecting rod large end bearing.

DESCRIPTION OF SYMBOLS 1 ... Roller 2, 2A ... Cage 3 ... Pocket 4 ... Base plating layer 5 ... Laminated plating layer 5a, 5c ... Ni / PTFE plating layer 5b ... Plating layer 50, 50A, 50B ... Roller with cage

Claims (11)

In a roller with a cage provided with a plurality of rollers and a ring-shaped cage having a pocket for holding each of the rollers at a plurality of locations in the circumferential direction,
A base plating layer is applied to the surface of the cage, a Ni / PTFE plating layer containing nickel and PTFE is provided on the surface of the base plating layer, and the same as the base plating layer is applied to the surface of the Ni / PTFE plating layer. Roller with a cage having a laminated plating layer composed of a plurality of plating layers each having a plating layer made of the above-described plating and a nickel / PTFE plating layer containing nickel and PTFE applied to the surface of the plating layer .   2. The roller with a retainer according to claim 1, wherein PTFE in each of the Ni · PTFE plating layers is one in which PTFE particles are dispersed during nickel plating.   3. The roller with a cage according to claim 1, wherein the plating layer made of the same plating as the base plating layer in the laminated plating layer, and the base plating layer is a nickel plating layer. 4.   4. The roller with a retainer according to claim 1, wherein a thickness of the plating layer is 3 μm or more and 10 μm or less, and a thickness of the Ni / PTFE plating layer is 5 μm or more and 15 μm or less.   The roller with a retainer according to any one of claims 1 to 4, wherein the PTFE amount in the Ni / PTFE plating layer is different for each Ni / PTFE plating layer.   The roller with a retainer according to any one of claims 1 to 5, wherein the base plating layer is a plating layer that does not include PTFE, and the outermost layer of the laminated plating layer is a plating layer that includes PTFE. .   The roller with a retainer according to any one of claims 1 to 6, wherein each plating layer in the laminated plating layer has a different thickness for each plating layer.   The roller with a retainer according to any one of claims 1 to 7, wherein the laminated plating layer includes three or more plating layers.   A roller bearing with a cage, comprising: the roller with a cage according to any one of claims 1 to 8; and a bearing ring on which the plurality of rollers roll.   A retainer in a roller with a retainer comprising a plurality of rollers and a ring-shaped retainer having a pocket for retaining each of the rollers at a plurality of locations in the circumferential direction, and a base on the surface of the retainer A cage in which a plating layer is applied and a laminated plating layer composed of a plurality of plating layers is applied to the surface of the underlying plating layer.   A bearing for a connecting rod large end of an engine using the roller with a cage according to any one of claims 1 to 8.

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