Patent · US Expired

Gaseous fuel flow rate detecting system

US5259355A · kind A · utility

16Cited by
18References
3Claims
0Family size

Assignees

Inventors

Key dates

Filing dateApr 7, 1992
Grant dateNov 9, 1993
Priority date
Expiry dateApr 7, 2012

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02M2025/0845
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A fuel evaporative emission flow rate detecting system is capable of detecting a small flow rate of the fuel evaporative emission. The system includes an electromagnetic valve (22) in a communication passage (21). The pressure of the fuel evaporative emission in the fuel tank is detected by means of a magnetic flux detector or so forth. A control circuit is responsive to the pressure of the fuel evaporative emission reaching 15 mmHg, for example, while the communication passage (21) is held closed, to open the communication passage (21). On the other hand, the control circuit closes the communication passage when the pressure of the fuel evaporative emission becomes lower than or equal to 8 mmHg. Depending on a period, in which the communication passage (21) is held open, the flow rate of the fuel evaporative emission is calculated.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.