fuel injection valve

Abstract

Provided is a fuel injection valve where it is possible to suppress the occurrence of a damage on a valve seat portion of a control valve of a back pressure control part caused by a foreign substance in high pressure fuel. An inlet connector having an introducing passage for high pressure fuel is mounted on an inlet opening portion of a housing, a fuel chamber is formed between an end surface portion of the inlet connector and a bottom surface portion of the inlet opening portion, a first fuel passage which communicates with a nozzle side opens at an outer peripheral portion of the bottom surface portion within a region of the fuel chamber, and a second fuel passage which communicates with a back pressure control part side opens at a center portion, and the inlet connector is configured such that high pressure fuel introduced into the fuel chamber from the inlet connector is capable of forming a swirl flow.

Description

Technical field [0001] The present invention relates to a fuel injection valve used in an accumulator fuel injection control device of an internal combustion engine. Background technique [0002] Conventionally, there has been known a fuel injection valve for injecting high-pressure fuel supplied from a common rail (accumulator) to a cylinder of the internal combustion engine used in an accumulator fuel injection control device of an internal combustion engine. The fuel injection valve has a structure including a housing, a nozzle body, a valve needle, and a back pressure control unit. [0003] The fuel injection valve includes an inlet connector connected to a high-pressure pipe. The other end of the high-pressure pipe is connected to the common rail, and high-pressure fuel is introduced into the fuel injection valve via a fuel passage formed in the inlet connector. The introduced high-pressure fuel is supplied to the fuel injection hole side provided in the nozzle body, and is a...

AI Technical Summary

Problems solved by technology

[0009] However, the structure of the filter described in Patent Document 1 has a length in the axial direction of the inlet connector, and there is a possibility that foreign matter larger than the gap formed can pass through.

In addition, the filter described in Patent Document 2 also has a limit in reducing the size of the formed pores, and it is difficult to capture foreign matter in units of several micrometers (μm) that reaches the fuel injection valve.

[0010] In particular, in recent years, the performance of the fuel main filter installed at a place other than the fuel injection valve in the accumulator-type fuel injection control device has improved, and the foreign matter reaching the fuel injection valve is smaller than the clearance of the filter structure of the fuel injection valve. Small, the structure of the existing filter is difficult to capture foreign matter in the fuel

Furthermore, due to the further increase in fuel pressure to cope with the severe exhaust gas restrictions in recent years, there is a possibility that the erosion of the valve seat surface of the control valve of the back pressure control unit caused by the above-mentioned foreign matter may be accelerated.

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