Automatic transmission fluids and additives therefor
US5441656A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 25, 1994 |
| Grant date | Aug 15, 1995 |
| Priority date | — |
| Expiry date | Jul 25, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10N2040/08
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
An effective way is described for overcoming the shudder problem associated with continuous slip torque converter clutches for use in automatic transmissions, especially shudder which occurs with new friction materials before break-in. To do this, an ATF is used in which the friction modifier system consists essentially of (i) an N-aliphatic hydrocarbyl-substituted diethanolamine in which the N-aliphatic hydrocarbyl-substituent is at least one straight chain aliphatic hydrocarbyl group free of acetylenic unsaturation and having in the range of 14 to 20 carbon atoms, and (ii) an N-aliphatic hydrocarbyl-substituted trimethylenediamine in which the N-aliphatic hydrocarbyl-substituent is at least one straight chain aliphatic hydrocarbyl group free of acetylenic unsaturation and having in the range of about 14 to about 20 carbon atoms. The ATF is devoid of any tertiary amine friction modifier component and any C.sub.12-36 aliphatic hydrocarbyl succinimide or succinamide friction modifier. Specified relative proportions and concentrations of (i) to (ii) are used.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.