Top-of-rail lubrication rate control by the hydraulic pulse width modulation method
US6076637A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 23, 1998 |
| Grant date | Jun 20, 2000 |
| Priority date | — |
| Expiry date | Feb 23, 2018 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB61K3/00
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A lubrication system for a railroad locomotive applies a lubricant with great accuracy in computer-controlled, precise quantities behind the last axle of the last locomotive such that the lubricant is consumed by the time the entire train has passed under all track, speed, temperature and train size conditions. Hydraulic pulse-width modulation (PWM or % PWM) controls the quantity of lubricant delivered. Time is divided into a series of windows each consisting of a few seconds. Lubricant delivered from a pressurized tank through long hoses to a solenoid controlled valve is then metered by the duration within this time window for which the computer computes and opens the valve. Compensation is provided for train tonnage and lubricant temperature as well as track curvature and train speed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.