Grease composition for a constant-velocity joint

Patent metadata

Field	Value
Publication number	US-11279899-B2
Application number	US-202117218252-A
Country	US
Kind code	B2
Filing date	Mar 31, 2021
Priority date	Mar 31, 2020
Publication date	Mar 22, 2022
Grant date	Mar 22, 2022

Abstract

A grease composition for a constant-velocity joint includes a mineral oil, a thickener, a molybdenum dithiocarbamate, a potassium borate hydrate, and a zinc dialkyldithiophosphate, wherein a content of the molybdenum dithiocarbamate is 1.2% by mass or more and 8% by mass or less, a content of the zinc dialkyldithiophosphate is 0.3% by mass or more and 2.0% by mass or less, and a content of the potassium borate hydrate is 0.28% by mass or more and 1.9% by mass or less, and wherein a mass ratio of the content of the molybdenum dithiocarbamate to the content of the potassium borate hydrate (molybdenum dithiocarbamate/potassium borate hydrate) is 2 or more and 13 or less, and a mass ratio of the content of the zinc dialkyldithiophosphate to the content of the potassium borate hydrate (zinc dialkyldithiophosphate/potassium borate hydrate) is 0.5 or more and 3.6 or less.

First claim

The invention claimed is:

1. A grease composition for a constant-velocity joint, the grease composition comprising:
a mineral oil,
a thickener,
a molybdenum dithiocarbamate,
a potassium borate hydrate, and
a zinc dialkyldithiophosphate,

wherein
a content of the molybdenum dithiocarbamate based on a total amount of the grease composition is 1.2% by mass or more and 8% by mass or less,
a content of the zinc dialkyldithiophosphate based on the total amount of the grease composition is 0.3% by mass or more and 2.0% by mass or less, and
a content of the potassium borate hydrate based on the total amount of the grease composition is 0.28% by mass or more and 1.9% by mass or less, and wherein
a mass ratio of the content of the molybdenum dithiocarbamate to the content of the potassium borate hydrate (molybdenum dithiocarbamate/potassium borate hydrate) is 2 or more and 13 or less,
a mass ratio of the content of the zinc dialkyldithiophosphate to the content of the potassium borate hydrate (zinc dialkyldithiophosphate/potassium borate hydrate) is 0.5 or more and 3.6 or less,
a mass ratio of the content of the molybdenum dithiocarbamate to the content of the zinc dialkyldithiophosphate (molybdenum dithiocarbamate/zinc dialkyldithiophosphate) is 3 or more, and
the thickener is a urea-based thickener represented by a formula (2):

in the formula (2), R4 represents a divalent aromatic hydrocarbon group having 6 to 15 carbon atoms, R5 represents a cyclohexyl group or a cyclohexyl derivative group having 7 to 12 carbon atoms, and R6 represents an alkyl group or alkenyl group having 8 to 20 carbon atoms.

2. The grease composition for a constant-velocity joint according to claim 1 ,
wherein the mass ratio of the content of the molybdenum dithiocarbamate to the content of the potassium borate hydrate (molybdenum dithiocarbamate/potassium borate hydrate) is 2 or more and 8 or less, and
the mass ratio of the content of the zinc dialkyldithiophosphate to the content of the potassium borate hydrate (zinc dialkyldithiophosphate/potassium borate hydrate) is 0.7 or more and 3.6 or less.

3. The grease composition for a constant-velocity joint according to claim 1 ,
wherein a content of the mineral oil based on the total amount of the grease composition is 50% by mass or more and 90% by mass or less, and
a content of the thickener based on the total amount of the grease composition is 2% by mass or more and 30% by mass or less.

4. The grease composition for a constant-velocity joint according to claim 1 ,
wherein the mass ratio of the content of the molybdenum dithiocarbamate to the content of the potassium borate hydrate (molybdenum dithiocarbamate/potassium borate hydrate) is 2 or more and 8 or less, and
the mass ratio of the content of the zinc dialkyldithiophosphate to the content of the potassium borate hydrate (zinc dialkyldithiophosphate/potassium borate hydrate) is 0.7 or more and 3.6 or less.

5. The grease composition for a constant-velocity joint according to claim 1 ,
wherein a content of the mineral oil based on the total amount of the grease composition is 50% by mass or more and 90% by mass or less, and
a content of the thickener based on the total amount of the grease composition is 2% by mass or more and 30% by mass or less.

6. The grease composition for a constant-velocity joint according to claim 2 ,
wherein a content of the mineral oil based on the total amount of the grease composition is 50% by mass or more and 90% by mass or less, and
a content of the thickener based on the total amount of the grease composition is 2% by mass or more and 30% by mass or less.

7. The grease composition for a constant-velocity joint according to claim 4 ,
wherein a content of the mineral oil based on the total amount of the grease composition is 50% by mass or more and 90% by mass or less, and
a content of the thickener based on the total amount of the grease composition is 2% by mass or more and 30% by mass or less.

Assignees

• Honda Motor Co Ltd
• Eneos Corp

Inventors

• Kusakai Katsuhito
• Suzuki Yasuo
• Matsuoka Kazuya
• Izumi Toru
• AYAME Yusuke

Classifications

• C10M2215/044

  having cycloaliphatic groups · CPC title

• C10M2203/1006

  used as base material · CPC title

• C10M2219/068

  Thiocarbamate metal salts · CPC title

• C10M135/18

  thiocarbamic type, e.g. containing the groups [IMAGE cpc-sch-C10M-1027.gif] · CPC title

• C10N2050/10

  semi-solid; greasy · CPC title