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:
Nov. 11, 1980
Filed:
Dec. 06, 1978
Robert S Migrin, Dearborn, MI (US);
Jerry A Olson, Dearborn, MI (US);
Eaton Corporation, Cleveland, OH (US);
Abstract
A low pressure drop air flowmeter for an automobile engine is disclosed. The meter contains a main air flow passage, a relatively small venturi to receive a portion of the air flow, pressure ports for sensing stagnation and static pressure and a set of swirl vanes disposed adjacent the outlet of the venturi and operative to impart a swirl to 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 pressure without appreciably increasing the pressure drop across the flowmeter. A tertiary passage provides a path of fluid communication between points upstream and downstream of the swirl vanes. This passage can be selectively opened or restricted by a valve which, in the preferred embodiment of the invention, opens the tertiary passage with increasing overall flow rate. This arrangement results in a fluid flowmeter having a characteristic pressure drop which is less than that of a conventional device, particularly at high flow rates. Also disclosed is a solenoid valve operative to selectively sample stagnation pressure in the tertiary 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.