The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 13, 1982
Filed:
Sep. 15, 1980
Jerry A Olson, Dearborn, MI (US);
Eaton Corporation, Cleveland, OH (US);
Abstract
A low pressure drop air flowmeter (10) for an automotive engine is disclosed. The meter includes a main air flow passage (26), a relatively small venturi tube (28) receiving a portion of the air flow, a pressure port (74) for sensing stagnation pressure in the main passage, a pressure port (70) for sensing static pressure in the throat of the venturi, and a complimentary pair of sets of stationary swirl vanes (30 & 32) disposed adjacent the outlet of the venturi and operative to jointly impart a swirl through the remainder of the air in the main passage, thereby creating a reduced pressure at the venturi outlet for amplifying the pressure difference between the stagnation and static pressures without appreciably increasing the pressure drop across the flowmeter. The sets of swirl vanes are rotationally displaceable with respect to one another, allowing some of the air to bypass the effect of the swirl vanes without being diverted to a separate passageway. This arrangement results in a fluid flowmeter having a characteristic pressure drop which is less than that for a conventional device, particularly at high flow rates, and which can be easily reconfigured to suit a specific application. Also disclosed is a solenoid valve (54) operative to selectively sample stagnation pressure in the main flow passage and signal pressure in the throat of the venturi and generate an electrical output signal as a function of the difference between these two pressure signals.