Unlock instant, AI-driven research and patent intelligence for your innovation.

Leak detecting device for fuel vapor treatment unit

A technology of leak detection device and processing unit, which is applied in the directions of adding non-fuel substances to fuel, using liquid/vacuum degree for liquid tightness measurement, charging system, etc., can solve problems such as leak diagnosis

Active Publication Date: 2005-12-07
NISSAN MOTOR CO LTD
View PDF2 Cites 20 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Therefore, it is sometimes difficult to correctly diagnose leaks with the conventional techniques described above because the pressure inside the evaporation system is not always positive.

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
  • Leak detecting device for fuel vapor treatment unit
  • Leak detecting device for fuel vapor treatment unit
  • Leak detecting device for fuel vapor treatment unit

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0016] refer to figure 1 The structure of the leak detection device in the first embodiment will be described. This leak detection device detects fuel vapor leakage from the evaporation system 1 of the fuel vapor processing unit. The fuel vapor processing unit purges the vapor gas generated in the fuel tank 2 to the intake pipe (or intake system) 22 of the engine 21 . The evaporation system 1 is composed of various parts arranged from the fuel tank 2 to the ventilation valve 7 .

[0017] The evaporation system 1 of the fuel evaporation processing unit includes a fuel tank 2 , a vent pipe 3 connected to the fuel tank 2 , and a carbon canister 4 connected to the fuel tank 2 via the vent pipe 3 . The canister 4 accommodates an adsorbent 4 a such as activated carbon for adsorbing vapor gas. An external air opening passage 11 is provided opposite to the connecting portion of the canister 4 and the vent pipe 3 . The steam gas is transported to the bottom of the carbon canister 4...

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

No PUM Login to View More

Abstract

Disclosed is a leak detecting device for a fuel vapor treatment unit that purges a vapor gas generated through evaporation of fuel in a fuel tank ( 2 ) into an intake system ( 22 ) of an engine ( 21 ). The leak detecting device includes a valve ( 5 ) that can selectively seal the fuel vapor treatment unit; a pressure detecting sensor ( 8 ) that detects a pressure in the fuel vapor treatment unit; and a controller ( 10 ). The controller ( 10 ) is programmed to: issue a command to close the valve ( 5 ) with a view to sealing the fuel vapor treatment unit during stoppage of the engine ( 21 ); calculate deviation amounts (P-P0) of the detected pressures during stoppage of the engine ( 21 ) after the fuel vapor treatment unit has been sealed; integrate absolute values (|P-P0|) of the deviation amounts, and determine, based on an integrated value (s), whether or not there is a leak occurring in the fuel vapor treatment unit.

Description

technical field [0001] The present invention relates to a leak detection device for detecting a malfunction of a fuel vapor treatment unit for treating fuel vapor. More specifically, the fuel vapor processing unit is used to purge fuel vapor generated from a fuel tank mounted on a vehicle to an air intake system of an engine. The detecting device detects leakage of fuel vapor from the fuel vapor processing unit. Background technique [0002] JP2003-56416 A published by the Japan Patent Office in 2003 discloses a conventional leak diagnosis device (or leak detection device) for a fuel vapor processing unit. This leakage diagnosis device periodically accumulates the detected internal pressure of the evaporation system, and makes a judgment of leakage from the evaporation system based on the accumulated value. Here, the period for leak diagnosis is a period during which the "positive pressure" ("positive pressure") is maintained when the evaporation system is sealed immediate...

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(China)
IPC IPC(8): F02M25/08
CPCF02M25/0827
Inventor 林孝根露木毅石井裕也
Owner NISSAN MOTOR CO LTD