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:
Oct. 05, 1999
Filed:
Apr. 24, 1997
George M Harpole, Torrance, CA (US);
Michael B Petach, Redondo Beach, CA (US);
Nelson P Mark, Long Beach, CA (US);
TRW Inc., Lyndhurst, OH (US);
Abstract
An apparatus comprises a reservoir (14) containing hydraulic fluid (68), a gear pump (16) with a suction hole (74), and a hydraulic muffler (18). The gear pump (16) has gears (78) with meshing teeth (80) that convey a flow of hydraulic fluid (68) from the reservoir (14) into the pump (16) through the suction hole (74). The muffler (18) attenuates noise by damping flow rate fluctuations that are caused by the meshing gear teeth (80). The muffler (18) includes a compliant element (92) and a fluid inertia structure (90) interposed between the suction hole (74) and the fluid (68) in the reservoir (14). The inertia structure (90) responds to the flow rate fluctuations by directing corresponding hydraulic pressure fluctuations to deflect the compliant element (92). As a result, noise is attenuated upon deflection of the compliant element (92).