Lubricating oil composition, and precision reduction gear using same

Patent metadata

Field	Value
Publication number	US-2019100712-A1
Application number	US-201716086409-A
Country	US
Kind code	A1
Filing date	Mar 31, 2017
Priority date	Mar 31, 2016
Publication date	Apr 4, 2019
Grant date	—

Abstract

Provided are a lubricating oil composition containing a base oil and a specific thiophosphate compound (A) and not substantially containing a molybdenum-based, and a precision reduction gear using the lubricating oil composition. The lubricating oil composition and the precision reduction gear using it exhibit excellent wear resistance and can prevent sludge generation in a broad range of contact pressures ranging from high to low.

First claim

1 . A lubricating oil composition, comprising a base oil and a thiophosphate compound (A) represented by the following general formula (I) and not substantially containing a molybdenum-based compound:

wherein R 1 , R 2 and R 3 each independently represent an aryl group having 6 to 12 ring carbon atoms, and the aryl group may be substituted with an alkyl group having 1 to 3 carbon atoms.

2 . The lubricating oil composition according to claim 1 , wherein the molybdenum atom-equivalent content of the molybdenum-based compound is less than 100 ppm by mass based on the total amount of the lubricating oil composition.

3 . The lubricating oil composition according to claim 1 , wherein the component (A) is a thiophosphate compound (A1) represented by the following general formula (II):

wherein R 4 , R 5 and R 6 each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

4 . The lubricating oil composition according to claim 1 , wherein the content of the component (A) is, based on the total amount of the lubricating oil composition, 0.1% by mass or more and 1.0% by mass or less.

5 . The lubricating oil composition according to claim 1 , further containing a phosphate compound (B) not containing a sulfur atom.

6 . The lubricating oil composition according to claim 5 , wherein the content of the component (B) is, based on the total amount of the lubricating oil composition, 0.1% by mass or more and 1.5% by mass or less.

7 . The lubricating oil composition according to claim 1 , further comprising a sulfur-based compound (C) containing 2 or more sulfur atoms in the molecule and not containing a phosphorus atom.

8 . The lubricating oil composition according to claim 7 , wherein the content of the component (C) is, based on the total amount of the lubricating oil composition, 0.01% by mass or more and 1% by mass or less.

9 . The lubricating oil composition according to claim 1 , having a kinematic viscosity at 40° C. of 40 mm 2 /s or more.

10 . The lubricating oil composition according to claim 1 , which is adapted to function as a lubricating oil composition for lubricating used in precision reduction gears.

11 . A precision reduction gear, comprising the lubricating oil composition of claim 1 .

12 . The precision reduction gear of claim 11 , which is incorporated in industrial robots.

13 . A method for producing a lubricating oil composition, the method comprising blending a base oil and a thiophosphate compound (A) represented by the following general formula (I), but not comprising a step of blending a molybdenum-based compound:

to obtain the lubricating oil composition, wherein R 1 , R 2 and R 3 each independently represent an aryl group having 6 to 12 ring carbon atoms, and the aryl group may be substituted with an alkyl group having 1 to 3 carbon atoms.

Assignees

• Idemitsu Kosan Co

Inventors

• Ono Takuya

Classifications

• C10N2040/04

  Oil-bath; Gear-boxes; Automatic transmissions; Traction drives · CPC title

• C10N2030/06

  Oiliness; Film-strength; Anti-wear; Resistance to extreme pressure · CPC title

• C10N2040/06

  Instruments or other precision apparatus, e.g. damping fluids · CPC title

• C10N2020/02

  Viscosity; Viscosity index · CPC title

• C10N2030/56

  Boundary lubrication or thin film lubrication · CPC title