US 7,600,320 B2
Method for manufacturing hydro dynamic bearing device
Masayuki Kaimi, Kuwana (Japan); Kazuto Shimizu, Kuwana (Japan); Kimihiko Bitou, Kuwana (Japan); Nao Ishiyama, Kuwana (Japan); and Nobuyoshi Yamashita, Kuwana (Japan)
Assigned to NTN Corporation, Osaka-Fu (Japan)
Filed on Mar. 10, 2006, as Appl. No. 11/373,225.
Application 11/373225 is a division of application No. 10/402321, filed on Mar. 28, 2003, granted, now 7,040,019.
Prior Publication US 2006/0150414 A1, Jul. 13, 2006
Int. Cl. B21K 1/10 (2006.01)
U.S. Cl. 29—898.02  [29/898; 33/517; 356/614; 356/615; 356/622; 356/908] 1 Claim
OG exemplary drawing
 
1. A method for manufacturing a hydro dynamic bearing device including a housing, an axial member housed in the housing, a radial bearing part for supporting the axial member in a non-contact manner in a radial direction by a hydro dynamic pressure action of a lubricating oil generated in a radial bearing clearance, and a seating part formed on one end part of the housing, the method comprising the step of measuring an oil-level height of the lubricating oil in the housing by laser displacement determining means that is arranged at a position a predetermined distance away from the sealing part of the housing,
detecting a distance from a standard position of the laser displacement determining means to the sealing part and a distance from the standard position of the laser displacement means to the oil-level height, and
based on a comparison result between the two detected distances, detecting the oil-level height of the lubricating oil in the housing.