Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Lithium Grease Composition Sealed in a Small Motor Bearing to Reduce Noise

a technology for reducing noise and grease, applied in the direction of lubricant composition, shaft and bearing, mechanical equipment, etc., can solve the problems of lithium-soap-ester grease, quick change of rotation speed of devices, and affecting recording media, so as to reduce the noise of the rotation of the motor

Inactive Publication Date: 2008-12-11
IWAMATSU HIROKI +3
View PDF5 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0005]According to the invention, a noise reducing grease composition and a sealed bearing containing the composition are provided. The bearing is desirably used for small motors particularly for home electronic appliances for example air conditioners, a motor for information equipment such as a hard disk driver and the like, and sealed in a bearing for a small motor to reduce the rotation noise of the motor. The present invention provides a grease composition composed of 5 to 20% preferably greater than 5% and less than 20% by weight of a lithium soap thickener. The thickener is synthesized from lithium hydroxide and a higher fatty acid with 10 to 20 carbon atoms or a higher hydroxyfatty acid with one or more hydroxyl groups and 10 or more carbon atoms, or both. Desirably, the lithium soap thickener accounts for about 7.5% to about 17.5% by weight of the grease composition preferably about 10% to about 15% particularly about 12% to about 13% by weight.

Problems solved by technology

Such devices makes a quick change in its rotation speed.
This lithium-soap-ester grease, however, tends to spatter and has a problem of damaging a recording medium if it is used as is.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Lithium Grease Composition Sealed in a Small Motor Bearing to Reduce Noise
  • Lithium Grease Composition Sealed in a Small Motor Bearing to Reduce Noise
  • Lithium Grease Composition Sealed in a Small Motor Bearing to Reduce Noise

Examples

Experimental program
Comparison scheme
Effect test

examples 1-13

OF THE INVENTION

[0030]As a thickener, a lithium soap synthesized from lithium hydroxide, stearic acid and 12-hydroxysteraric acid was employed.

[0031]As a base oil, a polymer ester oil with a viscosity (40° C.) of approximately 140 mm2 / s was used. As a synthetic ester oil, a tetraester oil and / or diester oil were used. DOS (di-2-ethylhexyl sebacate) was used as a diester oil, and PE (pentaerythritol ester) was used as a tetraester oil.

[0032]As a synthetic hydrocarbon oil, poly-α-olefin oil was used.

[0033]As a synthetic ether oil, an alkyl diphenyl ether oil was used.

[0034]Alkyl diphenylamine was employed as an antioxidant and calcium sulphonate was employed as an anticorrosive agent.

[0035]The components were mixed in ratios as shown in Table 1, and heated to 220 to 230° C. while being stirred until the entire mixture became fluid. The solution was poured into a stainless steel container so as to form a depth of 3 to 5 mm and cooled to 50° C. or lower. A grease composition was obtaine...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
weightaaaaaaaaaa
noiseaaaaaaaaaa
viscosityaaaaaaaaaa
Login to View More

Abstract

A lithium grease composition which can be sealed in a small motor bearing to reduce noise, composed of 5-20% by weight of a thickener and 95-80% by weight of a base oil, wherein said grease composition adopts lithium soap as the thickener, which is synthesized from lithium hydroxide and a higher fatty acid with 10 to 20 carbon atoms and / or a higher hydroxyfatty acid with one or more hydroxyl groups and 10 or more carbon atoms, and the base oil includes, as a main component, a polymer ester oil (A) in which 8 or more ester groups are arranged in a comb tooth form on one side of chain molecules constituted by eight or more carbon atoms which is expressed by general formula 1: (In the formula, each of R1, R2, R3 and R4 is an alkyl group, where x is an integer and x≧2, and y is an integer and y≧2.) and the base oil (40 C) has a viscosity of 25 to 80 mm2 / s.

Description

TECHNICAL FIELD[0001]The present invention relates to a grease composition for motor bearings for small motors, particularly home electric appliances such as an air conditioner, motor bearings for information equipment such as a hard disk driver and the like, and more specifically to a noise reduction grease sealed in a bearing for a small motor to reduce the rotation noise of the motor.BACKGROUND ART[0002]Generally the use of greases sealed in a bearing is known. The prior art shows a grease composition in which 8 or more ester groups are arranged in a comb tooth form on one side of the chain molecules of oil composed of 8 or more carbon atoms. The grease is formed by adding a urea thickener to a base oil in which a synthetic hydrocarbon oil and a synthetic ester oil are mixed in a weight ratio of 0.65-0.75:0.35-0.25. See Japanese Patent No. 3514574 and U.S. Pat. No. 5,910,470. This grease is sealed in a ball bearing that supports a belt driven pulley placed in the vicinity of an a...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(United States)
IPC IPC(8): C10M145/16
CPCC10M169/02C10M2205/028C10M2205/0285C10M2207/04C10M2207/0406C10M2207/1265C10M2207/1285C10M2207/282C10M2207/2825C10M2207/283C10M2207/2835C10M2209/06C10M2209/0606C10M2215/064C10M2219/044C10N2230/76C10N2240/02F16C2380/26C10N2030/76C10N2040/02
Inventor IWAMATSU, HIROKIAKIYAMA, MOTOHARUMIYAMOTO, YASUHIROOKAMURA, SEIJI
Owner IWAMATSU HIROKI
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com