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:
Jun. 16, 1998
Filed:
Dec. 10, 1996
U.S. Philips Corporation, New York, NY (US);
Abstract
A dynamic groove bearing (9,89,111) with an inner bearing part (15) and an outer bearing part (17) which is rotatable about the inner bearing part (15). The bearing parts (15,17) are provided with cooperating bearing surfaces (23,35) between which a bearing gap (45) filled with liquid lubricant (75,105) is present. The bearing surface (35) of at least one of the bearing parts (17) is provided with a pattern of grooves (51,53). The bearing surface (35) of the outer bearing part (17) is provided with an annular recess (67, 91,113) which bounds the bearing gap (45). The annular recess (67, 91, 113) is asymmetrical, having at a side thereof facing the bearing gap (45) a first lateral surface (69) adjoining the bearing surface (35) of the outer bearing part (17) and enclosing an obtuse angle .beta..sub.1 with the bearing surface (35) of the outer bearing part (17). At a side remote from the bearing gap (45) the annular recess has a second lateral surface (71) which adjoins the bearing surface (35) of the outer bearing part (17) and encloses an obtuse angle .beta..sub.2 with respect thereto, the obtuse angle .beta..sub.1 being smaller than the obtuse angle .beta..sub.2. The annular recess (67, 91, 113) prevents leakage of the liquid lubricant (75, 105) from the bearing gap (45) at comparatively high speeds of the dynamic groove bearing (9, 89, 111). Such a bearing can be used in an electric motor (1, 87, 109) of a data storage unit (121) in which an information disc (123) such as, for example, a hard disk of a computer, is rotatable relative to a scanning unit (129) with a magnetic head (131) by means of the electric motor.