Rolling body, method for producing rolling body, and dynamic force transmission device

Patent metadata

Field	Value
Publication number	US-9834836-B2
Application number	US-201214130783-A
Country	US
Kind code	B2
Filing date	Jul 4, 2012
Priority date	Jul 5, 2011
Publication date	Dec 5, 2017
Grant date	Dec 5, 2017

Abstract

A high durability roller, a manufacturing method thereof and a power transmission device with the high durability roller are provided. The roller for a power transmission device that comprises a plurality of rollers in contact with each other directly or with lubricant between them, includes: a metal base having a Young's modulus of 220 GPa or less; and a coating that is formed on a surface of the metal base, includes hard particles and a metal component composed of at least either simple metal or alloy, and has a Young's modulus of 250 GPa or more. The power transmission device includes the roller. The method of manufacturing the roller includes: forming the coating on the surface of the metal base by thermal spraying using a thermal spray material that comprises the hard particles and the metal component composed of at least either simple metal or alloy.

First claim

The invention claimed is:

1. A roller for a power transmission device that comprises a plurality of rollers in contact with each other directly or with lubricant between them, comprising:
a metal base having a Young's modulus of 220 GPa or less; and
a coating that is formed on a surface of the metal base, comprises hard particles and a metal component comprising at least either simple metal or alloy, and has a Young's modulus of 250 GPa or more, and
the roller has an equivalent Young's modulus, as determined after the coating is formed on the metal base, of 200 GPa or more and 350 GPa or less, wherein the equivalent Young's modulus is determined according to the following equation (1):

E
2
*

=

E

2
⁢
c

*

⁢

1
-

(

λ
+
κ
+

4
⁢

κα
2

⁢

H
2

)

⁢

exp
⁡

(

-
2

⁢
α
⁢

⁢
H

)

+

λκexp
⁡

(

-
4

⁢
α
⁢

⁢
H

)

1
+

4
⁢

⁢
α
⁢

⁢
H
⁢

⁢

κexp
⁡

(

-
2

⁢
α
⁢

⁢
H

)

-

λ
⁢

⁢

κexp
⁡

(

-
4

⁢

⁢
α
⁢

⁢
H

)

(
1
)

wherein in the equation (1), E* 2 is the equivalent Young's modulus of the roller, E* 2c is the Young's modulus of the coating, H (=h/a 0s ) is the dimensionless coating thickness, h is the coating thickness, a 0s is the contact radius, wherein
α=wh/H, κ=(μ−1)/(μ+(3-4v c )), and λ=1−(4(1−v c ))/(1+μ(3−4v s )), wherein μ is the shear modulus ratio, and each of v c and v s is Poisson's ratio.

2. The roller according to claim 1 , wherein the coating has a sectional porosity of 5 vol % or less.

3. The roller according to claim 1 , wherein the hard particles are hard particles of at least one selected from a group consisting of carbides, borates, nitrides, silicates, sulfides, oxides and carbon.

4. The roller according to claim 1 , wherein the hard particles are hard particles of tungsten carbide.

5. The roller according to claim 4 , wherein the coating comprises a η phase.

6. A power transmission device, comprising the roller according to claim 1 .

Assignees

• Takashima Kazuhiko
• Nanbu Toshikazu
• Sakata Kazunori
• Tagomori Kouji
• Sugiyama Naoki
• Nissan Motor
• Fujikikosan Corp

Inventors

• Takashima Kazuhiko
• Nanbu Toshikazu
• Sakata Kazunori
• Tagomori Kouji
• Sugiyama Naoki

Classifications

• C23C4/129 Primary

  Flame spraying · CPC title

• F16H2055/325

  characterized by roughness or hardness of friction surface · CPC title

• C23C4/10

  Oxides, borides, carbides, nitrides or silicides; Mixtures thereof · CPC title

• C23C30/00

  Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process (C23C26/00, C23C28/00 take precedence) · CPC title

• C23C4/06 Primary

  Metallic material · CPC title