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:
Mar. 21, 1989
Filed:
Mar. 27, 1987
Toshiro Kawakami, Obu, JP;
Aisin Seiki Kabushiki Kaisha, Kariya, JP;
Abstract
In a Roots blower having a casing, two rotors rotatably housed within the casing, and at least two grease-enclosing bearing units to rotatably support the rotors, characterized in that a bypass groove is formed for each of the bearing unit so as to communicate between a first chamber defined by the casing and the rotors on the side of one axial end of the bearing unit and a second chamber formed by the casing and the bearing unit on the other axial side of the bearing unit, and in that a pair of pressure loaded seal rings (or lip seals) is disposed on axially opposite sides of the bearing unit in such a way that one periphery of each seat ring is secured to a stationary portion of the bearing unit and the other periphery thereof is free to move selectively into or out of contact with a movable portion of the bearing unit according to the presence or absence of a pressure difference produced by a delay in a pressure-balancing action of the bypass groove between the two chambers so that the seal ring prevents bearing grease from leaking. The seal ring is of a U- or L-shape.