Diesel engine fuel injection system with a rate-of-injection control arrangement
US4730585A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 25, 1986 |
| Grant date | Mar 15, 1988 |
| Priority date | — |
| Expiry date | Jun 25, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A fuel injection system comprising a fuel injection pump, at least one fuel injection nozzle connected thereto, and a control device for varying the rate of injection of the system according to varying engine parameters. The control device has a variable volume chamber, the volume of which is varied by a piston located by a piezoelectric actuator. The variable volume chamber and a pumping chamber of the pump is intermittently connected by a passage which is specifically designed in such a manner that the fluid communication between the chambers, during the delivery stroke of a pump plunger, is provided only for an initial stage of the delivery stroke. A rate of injection is controlled in the initial stage to perform a pilot injection. In the subsequent stage, in which there is no need for rate-of-injection control, the variable volume chamber is isolated from the pumping chamber in order to relieve the piezoelectric actuator from an excessively high fuel pressure that would cause degradation of the piezoelectric elements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.