Spindle unit
Patent 5388917 Issued on February 14, 1995. Estimated Expiration Date: 
September 28, 2013. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
September 28, 2013. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3620586 Mounting arrangement for a spindle Bearing device Mechanism for pre-loading bearings Device for preloading bearings Variable preload bearing apparatus Patent #: 5051005 InventorsAssigneeApplicationNo. 127608 filed on 09/28/1993US Classes:384/517, Axially biased race384/493Temperature compensationExaminersPrimary: Hannon, Thomas R.Attorney, Agent or FirmInternational ClassesF16C 035/12F16C 027/00 Foreign Application Priority Data1992-10-14 JPAbstractA spindle unit which can offset any displacement of the spindle due to thermal expansion and which can adjust the preload on the bearings according to the revolving speed of the spindle. Between the outer casing and the spindle are provided a high-rigidity elastic member and a pressure chamber connected to an oil pressure control valve. A displacement sensor provided at the end of the spindle and a tachometer are connected to the pressure control valve. As the revolving speed of the spindle increases, oil pressure is introduced into the pressure chamber to reduce the preload. By reducing the preload, the spindle moves axially, thus offsetting its displacement due to thermal expansion. | |
