Patent · US Expired

Process and apparatus for operating an internal combustion engine

US4408589A · kind A · utility

11Cited by

3References

4Claims

0Family size

Assignee

Robert Bosch GmbH · DE

Inventors

Peter Hauler · Karlsruhe, DE
Frieder Heintz · Blankenloch, DE
Erich Zabler · Blankenloch, DE

Key dates

Filing date	Jul 14, 1977
Grant date	Oct 11, 1983
Priority date	—
Expiry date	Jul 14, 1997

Classification

Technology area (CPC F)Mechanical Engineering; Lighting; Heating
CPC primaryF02D41/2096
WIPO fieldEngines, pumps, turbines
WIPO sectorMechanical engineering

Abstract

An ultrasonic transmitter is disposed on one wall inside the air induction tube of an internal combustion engine and an ultrasonic receiver is disposed on the opposite wall, downstream of the transmitter. A second transmitter-receiver pair is similarly located, but with the positions of transmitter and receiver reversed. Thus, the signals from one transmitter travel generally with the air flow, whereas the signals from the second transmitter travel generally against the air flow. Since the travel time of the signals depends on the velocity of the flowing air, the frequencies of signals from the two receivers are different and this difference is used to determine the air velocity and, hence, the air flow rate.

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